c++:用长整数加减乘除四则运算计算π值，精确到1000位或更多

最新推荐文章于 2025-01-26 00:15:00 发布
最新推荐文章于 2025-01-26 00:15:00 发布
阅读量752 收藏 1
点赞数
分类专栏： 代码 文章标签： c++
版权声明：本文为博主原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接和本声明。
本文链接：https://blog.youkuaiyun.com/ywqb95/article/details/120399347
版权

学习c++。把长整数转换成字符串，这样可以很长了。

用codeblocks 编写。如果用vs需要小改动一下。vs对类比较严格。

#include <iostream>
//#include <stdio.h>
using namespace std;
#define NUMLEN 10024   //must > 1
int compareBignum(const char*str1,const char*str2);
char* itoa(int num,char* str,int radix);  //整数转字符串
class Bignum
{
    char iNum[NUMLEN];
public:
    Bignum()
    {
        memset (iNum,'\0',NUMLEN);
       //iNum[0] = '\0';
       //iNum[1] = '\0';
    }

    Bignum(char * num)
    {
        int i;
            for(i=0; i< NUMLEN - 1;i++)
            {
                if(num[i] >= '0' && num[i] <= '9')
                {
                    iNum[i] = num[i];
                }
                else if(num[i]== '\0')
                {
                    iNum[i] = '\0';
                    break;
                }
                else
                {
                    iNum[0] = 'E';
                    iNum[1] = '\0';
                    break;
                }

            }
        //去掉前面的0
            if(iNum[0] == '0')
            {
                int num0=0;
                int len = strlen(iNum);
                for(i=0;i<len;i++)
                {
                    if(iNum[i] != '0')
                        break;
                    else
                        num0++;
                }
                for(i=0;i<len-num0;i++)
                {
                    iNum[i]=iNum[i+num0];
                }
                iNum[i]='\0';
                if(iNum[0] == '\0')
                {
                    iNum[0] = '0';
                    iNum[1] = '\0';
                }

        }
    }
public:
    Bignum operator +(const Bignum &str2) const {
        return jia(str2);
}

public:
    Bignum operator *(const Bignum &str2) const {

        return chen(str2);
    }
public:
    Bignum operator /(const Bignum &str2) const {

        return chu(str2);
    }
public:
    Bignum operator -( const Bignum &str2) const{

    return jian(str2);
}
    void display()
    {
      //  cout << "0="<<iNum[0] +'\12' << "  1="<< iNum[1] +'\12'<< endl;
        //cout << "this number is " << iNum << "   len=："<< len  << endl;
        printf("%s len=%d\n",iNum,strlen(iNum));
    }
public:
    bool operator ==(const Bignum &str2) const{
       unsigned int i;
        bool ret;
        if(strlen(iNum) == strlen(str2.iNum))
        {
            for(i=0;i<strlen(iNum);i++)
            {
                if(iNum[i] != str2.iNum[i])
                {
                  ret = false;
                  break;
                }
                ret = true;

            }
        }
        return ret;
    }
public:
    bool operator > (const Bignum &str2) const{
       unsigned int i;
        bool ret;
        if(strlen(iNum) > strlen(str2.iNum))
            ret = true;
        else
            if(strlen(iNum) < strlen(str2.iNum))
            {
                ret = false;
            }
            else
                {
                for(i=0;i<strlen(iNum);i++)
                {
                    if(iNum[i] > str2.iNum[i])
                    {
                    ret = false;
                    break;
                    }
                    ret = true;

                }
            }
        return ret;
    }
public:
    bool operator < (const Bignum &str2) const{
        unsigned int i;
        bool ret;
        if(strlen(iNum) < strlen(str2.iNum))
            ret = true;
        else
            if(strlen(iNum) > strlen(str2.iNum))
            {
                ret = false;
            }
            else
                {
                for(i=0;i<strlen(iNum);i++)
                {
                    if(iNum[i] < str2.iNum[i])
                    {
                    ret = false;
                    break;
                    }
                    ret = true;

                }
            }
        return ret;
    }
Bignum jian(const Bignum &str2) const
{
    Bignum temp;
    if(iNum[0] == 'E' || str2.iNum[0] == 'E' || iNum[NUMLEN-2] == 'E' || str2.iNum[NUMLEN-2] == 'E' )
    {
        temp.iNum[0] = 'E';
        temp.iNum[1] = '\0';
        temp.iNum[NUMLEN-2]='E';
        temp.iNum[NUMLEN-1]='\0';
        return temp;
    }
    int duo ;
    char k,jie;
    int pos;
    int len,len2,i;

    int comp = compareBignum(iNum,str2.iNum);
    if( comp== 1)
    {
      //  cout << "zhengshu" <<endl;
        jie = '\0';
        len = strlen(iNum);
        len2 = strlen(str2.iNum);
        duo = len - len2;
        pos = len - 1;
        for(i=len2 - 1;i>=0;i--) //123456 123 6 3
        {
            if(str2.iNum[i] >(iNum[i+duo] - jie))
            {
                k = '\12' +iNum[i+duo] - str2.iNum[i] -jie ; // '\12'+str1.iNum[i+duo] -'0' - (str2.iNum[i]-'0')
                jie = '\1';
            }
            else
            {
                k = iNum[i+duo] - str2.iNum[i] - jie;
                jie = '\0';
            }
            temp.iNum[pos] = k +'0';

         //   cout << pos << ":"<<str2.iNum[i]<<":"<< iNum[i+duo]<< ":"<<temp.iNum[pos]<<endl;
            pos = pos - 1;
        }//123456 123 6 3
        for(i= len - len2 -1 ;i>=0;i-- )
        {
            if(iNum[i] == '0' && jie == '\1')
            {
                k = '\11';
                jie = '\1';
            }
            else
            {
                k = iNum[i] - '0' - jie;
                jie = '\0';
            }
            temp.iNum[pos] = k +'0';
      //      cout << pos << "*"<< iNum[i]<< ":"<<temp.iNum[pos]<<endl;

            pos = pos -1;
        }
        int num0=0;//去前面的0
        for(i=0;i<len;i++)
        {
            if(temp.iNum[i] == '0')
            {
                num0++;
            }
            else
            {
                break;
            }
        }
        if(num0>0)
        {
            for(i=num0;i<len;i++)
            {
                temp.iNum[i-num0]=temp.iNum[i];
            }
            temp.iNum[i-num0]= '\0';
        }
        else
        {
            temp.iNum[len] = '\0';
        }
    }
    else if(comp == -1 ) //先str2 - 本Bignum,再在前面加负号
    {
        //cout <<"fushu"<<endl;
        jie = '\0';
        len = strlen(iNum);
        len2 = strlen(str2.iNum);
        duo = len2 - len;
        pos = len2 - 1;
        for(i=len - 1;i>=0;i--) //1777
        {                       // 999
            if(iNum[i] > (str2.iNum[i+duo] - jie))
            {
                k = '\12' +str2.iNum[i+duo] - iNum[i] -jie ; // '\12'+str1.iNum[i+duo] -'0' - (str2.iNum[i]-'0')
                jie = '\1';
            }
            else
            {
                k = str2.iNum[i+duo] - iNum[i] - jie;
                jie = '\0';
            }
            temp.iNum[pos] = k +'0';

           // cout << pos << ":"<<str2.iNum[i+duo]<<":"<< iNum[i]<< ":"<<temp.iNum[pos]<<endl;
            pos = pos - 1;
        }
        for(i= len2 - len -1 ;i>=0;i-- ) //999 3 10011
        {
            if(str2.iNum[i] == '0' && jie == '\1')
            {
                k = '\11';  //八进制11等于十进制9
                jie = '\1';
            }
            else
            {
                k = str2.iNum[i] - '0' - jie;
                jie = '\0';
            }
            temp.iNum[pos] = k +'0';
          //  cout << pos << ":;"<<str2.iNum[i]<<":"<<temp.iNum[pos]<<endl;

            pos = pos -1;
        }
        int num0=0;//去前面的0
        for(i=0;i<len2;i++)
        {
            if(temp.iNum[i] == '0')
            {
                num0++;
            }
            else
            {
                break;
            }
        }
         //000123456 len2=9 num0=3 -123456
        if(num0>1)
        {
            for(i=num0;i<len2;i++)
            {
               temp.iNum[i-num0+1]=temp.iNum[i];
            }
          temp.iNum[0]= '-';
          temp.iNum[len2-num0+1] = '\0';
        }
        else if(num0==1)
        {
            //cout << -1 << endl;
            temp.iNum[0]='-';
            temp.iNum[len2]='\0';
        }
        else
        {
            for(i=len2;i>0;i--)
            {
                temp.iNum[i]=temp.iNum[i-1];
            }
            if(len2 <NUMLEN -2)
            {
                temp.iNum[0]='-';
                temp.iNum[len2+1]='\0';
            }
            else
            {
                 temp.iNum[0]='-';
                 temp.iNum[NUMLEN-2] = 'E';
                 temp.iNum[NUMLEN-1] = '\0';
            }

        }

    }
    else
    {
        temp.iNum[0]='0';
        temp.iNum[1]='\0';
    }
 return temp;
}

Bignum chen(const Bignum &str2) const //两个数大于等于0
{
   /* Bignum temp; //返回值
    Bignum temp2; //str2 的副本
    Bignum temp3;  //本值
    Bignum temp4("1");
    Bignum temp5;
    unsigned int i;
    if(iNum[0] == 'E' || str2.iNum[0] == 'E')
    {
        temp.iNum[0] = 'E';
        temp.iNum[1] = '\0';
        return temp;
    }
    if(str2.iNum[0]== '0' && str2.iNum[1]== '\0')
    {
        temp.iNum[0] = '0';
        temp.iNum[1] = '\0';
        return temp;
    }
    for(i=0;i<=strlen(iNum);i++)
    {
        temp.iNum[i] = iNum[i];
    }

    if(str2.iNum[0]== '1' && str2.iNum[1]== '\0')
    {
        return temp;
    }

    temp3 = temp;

    for(i=0;i<=strlen(str2.iNum);i++)
    {
        temp2.iNum[i] = str2.iNum[i];
    }

    while(temp2.iNum[0]!='1' || temp2.iNum[1]!='\0')
    {
        temp = temp + temp3;
        temp2 = temp2 - temp4;

        }*/

        //模拟乘法步骤
        int  i,k;
        int j;
        int e=0;  //指数代表位数
        Bignum temp0;//本数
        Bignum temp("0");  //返回值
        Bignum temp2;  //中间值
    //    cout <<"start1= " << str2.iNum<< endl;
        if(iNum[0] == 'E' || iNum[NUMLEN-2] == 'E' || str2.iNum[0]=='E' || str2.iNum[NUMLEN-2] == 'E')
        {
            temp.iNum[0] = 'E';
            temp.iNum[1] = '\0';
            return temp;
        }
  //     cout <<"start2= " << str2.iNum<< endl;

        for(i=0;i<(int)strlen(iNum);i++)
        {
            temp0.iNum[i] = iNum[i];
        }
   //     cout <<"start3= " << str2.iNum<< endl;

        temp0.iNum[i] = '\0';
     //    cout <<"start4 for temp0=" << temp0.iNum << "str2="<< str2.iNum<<endl;

        for(i=strlen(str2.iNum)-1;i>=0;i--)
        {
            //中间值归零
            temp2.iNum[0]='0';
            temp2.iNum[1]='\0';
            if(str2.iNum[i] == '0')
            {
      //        cout <<"start 0  " << i <<endl;

                temp2.iNum[0]='0';
                temp2.iNum[1]='\0';
            }
            else
            if(str2.iNum[i] == '1')
            {
       //        cout <<"start 1  " << i <<endl;

                temp2 = temp0;
            }
            else
            if(str2.iNum[i] == '2')
            {
           //     cout <<"start 2  " << i <<endl;
                temp2 = temp0 + temp0;
            }
            else
            if(str2.iNum[i] == '3')
            {
           //     cout <<"start 3  " << i <<endl;
                temp2 = temp0 + temp0 + temp0;
            }
            else
            if(str2.iNum[i] == '4')
            {
            //    cout <<"start 4  " << i <<endl;
                temp2 = temp0 + temp0;
                temp2 = temp2 + temp2;
            }
            else
            if(str2.iNum[i] == '5')
            {
           //     cout <<"start 5  " << i <<endl;
                temp2 = temp0 + temp0;
                temp2 = temp2 + temp2;
                temp2 = temp2 + temp0;
            }
            else
            if(str2.iNum[i] == '6')
            {
             //   cout <<"start 6  " << i <<endl;
                temp2 = temp0 + temp0;
                temp2 = temp2 + temp0;
                temp2 = temp2 + temp2;
            }
            else
            if(str2.iNum[i] == '7')
            {
             //   cout <<"start 7  "<< i  <<endl;
                temp2 = temp0 + temp0;
                temp2 = temp2 + temp0;
                temp2 = temp2 + temp2;
                temp2 = temp2 + temp0;
            }
            else
            if(str2.iNum[i] == '8')
            {
               // cout <<"start 8  " << i <<endl;
                temp2 = temp0 + temp0;
                temp2 = temp2 + temp2;
                temp2 = temp2 + temp2;
            }
            else
            if(str2.iNum[i] == '9')
            {
            //  cout <<"start 9  " << i <<endl;
                temp2 = temp0 + temp0;
                temp2 = temp2 + temp2;
                temp2 = temp2 + temp2;
                temp2 = temp2 + temp0;
            }
         //   cout <<"start e " << temp2.iNum << endl;
            if(e>0 &&  temp2.iNum[0]!='0')
            {
                if(temp2.iNum[0]!='E' && temp2.iNum[NUMLEN-2]!='E')
                {
                    k = strlen(temp2.iNum);
              //          cout <<" k=" << k <<endl;
                    if(e+k<NUMLEN-2)
                    {
                    for(j =0 ; j < e; j++)
                    {
                        temp2.iNum[k+j] = '0';

                    }
                    temp2.iNum[k+j] = '\0';
                    }
                    else
                    {
                      //  cout << "e="<<e<<" k="<<k<<endl;
                      temp2.iNum[NUMLEN-2]= 'E';
                      temp2.iNum[0]= 'E';
                      temp2.iNum[NUMLEN-1]= '\0';

                    }
                    }
            }
            if(temp2.iNum[NUMLEN-2]=='E')
            {
                //越界了
                temp.iNum[NUMLEN-2]='E';
                temp.iNum[0] = 'E';
                temp.iNum[NUMLEN-1] = '\0';
               // cout << "temp2=" << temp2.iNum << "len="<<strlen(temp2.iNum) << endl;
                break;
            }
            else
            {
                            temp = temp + temp2;
                            if(temp.iNum[NUMLEN-2] == 'E')
                            {
                                //temp.iNum[NUMLEN-1]='E';
                                temp.iNum[0] = 'E';
                                temp.iNum[NUMLEN-1] = '\0';
                               //  cout <<"temp ="<< temp.iNum <<endl;
                                 break;
                            }
            }
         //   cout << "temp2=" << temp2.iNum << "  temp=" << temp.iNum <<"  e="<<e << endl;
            e++;


        }


    return temp;

}

Bignum chu(const Bignum &str2) const //两个数大于等于0
{
    Bignum temp;//返回值
    Bignum temp0("5"); //试验值
    Bignum temp1;  //截取被除数长度
    Bignum yutemp; //余数
    int k;
    int pos = 0;//得数位置
    int pos1;   //原被除数被计算位置
    int len=(int)strlen(iNum);
    int len2=(int)strlen(str2.iNum);
    int len1;//temp1.iNum长度
 //   cout <<"iNum="<<iNum<<" str2="<< str2.iNum << endl;
    if(len < len2)

    {
        temp.iNum[0] ='0';
        temp.iNum[1] ='\0';
        return temp;
    }
        for(k=0;k<len2;k++)
        {
            temp1.iNum[k]=iNum[k];
        }
        temp1.iNum[len2] = '\0';//这时k=len2。
        if(compareBignum(temp1.iNum,str2.iNum) == -1) //小于被除数，就算到下一位
        {
            if(len2 < len)   //012345
            {
                temp1.iNum[len2]=iNum[len2]; //这时k=len2。
                temp1.iNum[len2+1]='\0';
                pos1 = len2;

            }
            else
            {
                temp.iNum[0] = '0';
                temp.iNum[1] = '\0';
                return  temp;
            }
        }
        else
        {
            pos1 = len2 - 1; //这时k=len2。pos1从0算起，所以减1.
        }

    while(true)
    {

   //cout << "temp1=" << temp1.iNum << "str2=" << str2.iNum <<"yutemp="<<yutemp.iNum<< "temp=" << temp.iNum<<endl;
        while(true)
        {
            temp0.iNum[0]='5';
            yutemp = temp1 - str2 * temp0;
            if(yutemp.iNum[0] == '-')  //5不足
            {
                temp0.iNum[0] = '3';
                yutemp = temp1 - str2 * temp0;
                if(yutemp.iNum[0] == '-')   //3不足
                {
                    temp0.iNum[0] = '2';
                    yutemp = temp1 - str2 * temp0;
                    if(yutemp.iNum[0] == '-') //2不足
                    {
                        yutemp = temp1 - str2;
                        temp.iNum[pos] = '1';
                        temp.iNum[pos+1] = '\0';
                        pos = pos + 1;
                        break;
                    }
                    else  //2有余
                    {
                        temp.iNum[pos] = '2';
                        temp.iNum[pos+1] = '\0';
                        pos = pos + 1;
                        break;

                    }
                }
                else        //3足 5不足
                {
                    temp0.iNum[0] = '4';
                    yutemp = temp1 - str2 * temp0;
                    if(yutemp.iNum[0] == '-') //4不足
                    {
                        temp0.iNum[0] = '3';
                        yutemp = temp1 - str2 * temp0;
                        temp.iNum[pos] = '3';
                        temp.iNum[pos+1] = '\0';
                        pos = pos + 1;
                        break;
                    }
                    else//4有余
                        {
                        temp.iNum[pos] = '4';
                        temp.iNum[pos+1] = '\0';
                        pos = pos + 1;
                        break;
                        }
                }
            }
            else  //5足
            {
                temp0.iNum[0] = '7';
                yutemp = temp1 - str2 * temp0;
                if(yutemp.iNum[0] == '-')   //7不足
                {
                    temp0.iNum[0] = '6';
                    yutemp = temp1 - str2 * temp0;
                    if(yutemp.iNum[0] == '-') //6不足
                    {
                        temp0.iNum[0] = '5';
                        yutemp = temp1 - str2 * temp0;
                        temp.iNum[pos] = '5';
                        temp.iNum[pos+1] = '\0';
                        pos = pos + 1;
                        break;
                    }
                    else  //6有余
                    {
                        temp.iNum[pos] = '6';
                        temp.iNum[pos+1] = '\0';
                        pos = pos + 1;
                        break;

                    }
                }
                else        //7足
                {
                    temp0.iNum[0] = '8';
                    yutemp = temp1 - str2 * temp0;
                    if(yutemp.iNum[0] == '-') //8不足
                    {
                        temp0.iNum[0] = '7';
                        yutemp = temp1 - str2 * temp0;
                        temp.iNum[pos] = '7';
                        temp.iNum[pos+1] = '\0';
                        pos = pos + 1;
                        break;
                    }
                    else//8有余
                    {
                        temp0.iNum[0] = '9';
                        yutemp = temp1 - str2 * temp0;
                        if(yutemp.iNum[0] == '-') //9不足
                        {
                            temp0.iNum[0] = '8';
                            yutemp = temp1 - str2 * temp0;
                            temp.iNum[pos] = '8';
                            temp.iNum[pos+1] = '\0';
                            pos = pos + 1;
                            break;
                        }
                    else //9足
                        {
                      //  yutemp = temp1 - str2 * temp0;
                        temp.iNum[pos] = '9';
                        temp.iNum[pos+1] = '\0';
                        pos = pos + 1;
                        break;
                        }
                    }
                }
            }

        }

        //重新算被除数
        if(pos1 == len -1)
        {
        // cout << "pos1 + len2 > len" << " pos1 =" << pos1 <<" len2=" <<len2 << " len=" <<len<<"pos="<< pos<< endl;
        //cout <<"2pos1 == len -1 ret=" << temp.iNum << endl;
        return temp;
        }
        if(yutemp.iNum[0]!='0')//余数不为0
        {
        for(k=0;k<(int)strlen(yutemp.iNum);k++)
        {
            //余数作为被除数的一部分
            temp1.iNum[k] = yutemp.iNum[k];
        }
        len1 =strlen(temp1.iNum);
        pos1 = pos1 + 1;
        temp1.iNum[k] = iNum[pos1];
        temp1.iNum[k+1] = '\0';

        while(compareBignum(temp1.iNum,str2.iNum) == -1) //小于被除数，就算到下一位
        {
            if(pos1 == len -1 )
            {
                temp.iNum[pos] = '0';
                temp.iNum[pos+1] = '\0';
                pos = pos + 1;
         //       cout << "pos1 == len -1" << endl;
         // cout <<"pos1 == len -1  ret="<<temp.iNum<<endl;
                return temp;
            }
        else
        {
            temp.iNum[pos] = '0';
            temp.iNum[pos+1] = '\0';
            pos = pos + 1;

            pos1 = pos1 + 1;
            k = k + 1;
            temp1.iNum[k] = iNum[pos1];
            temp1.iNum[k+1] = '\0';
        }
        }
        }
        else  //余数是0  1110  11 100
        {
      //    cout << "temp="<<temp.iNum << " len=" << len <<" pos1="<< pos1 <<" temp1="<<temp1.iNum<<endl;
            //如果当前值为0
            pos1 = pos1 + 1;
            while(iNum[pos1]=='0')
            {
                temp.iNum[pos] = '0';
                temp.iNum[pos+1] = '\0';
                pos1 = pos1 + 1;
                pos = pos + 1;
            }
         //   cout << "pos1=" <<pos1  <<"len=" <<len << endl;
               if(pos1 ==  len)
               {
                  //  cout <<"1pos1 ==  len ret="<<temp.iNum<<endl;
                   return temp;
               }

               for(k=0;k<len2-1;k++)
                {
                    temp1.iNum[k] = iNum[pos1];
                    temp1.iNum[k+1] = '\0';
                    pos1 = pos1 + 1;
                    temp.iNum[pos] = '0';
                    temp.iNum[pos+1] = '\0';
                    pos = pos + 1;
                    if(pos1 ==  len)
                    {
                         //  cout <<"pos1 ==  len ret="<<temp.iNum<<endl;

                        return temp;
                    }
                }
            //    cout << "temp1.iNum=" <<temp1.iNum << " pos="<<pos<<endl;
                    temp1.iNum[k] = iNum[pos1];
                    temp1.iNum[k+1] = '\0';
                    pos1 = pos1 + 1;

                if(compareBignum(temp1.iNum,str2.iNum)==-1)
                {
          //      cout <<"compareBignum(temp1.iNum,str2.iNum)==-1"<<endl;
                if(pos1 == len)
                {
                    temp.iNum[pos] = '0';
                    temp.iNum[pos+1] = '\0';
                    return temp;
                }
                else   // 1110111011  11
                {
                    temp.iNum[pos] = '0';
                    temp.iNum[pos+1] = '\0';
                    pos = pos + 1;

                    k = k+1;
                    temp1.iNum[k] = iNum[pos1];
                    temp1.iNum[k+1] = '\0';
                    pos1 = pos1 + 1;

                }
                }
                pos1 = pos1 - 1;



        }


    } //while
   // temp.iNum[pos] = '\0';
//   cout <<"ret="<<temp.iNum<<endl;
    return temp;

}

Bignum jia(const Bignum &str2) const
{
    Bignum temp;
    if(iNum[0] == 'E' || str2.iNum[0] == 'E')
    {
        cout << "iNum[0]= E"  << endl;
        temp.iNum[0] = 'E';
        temp.iNum[1] = '\0';
        temp.iNum[NUMLEN-2] = 'E';
        temp.iNum[NUMLEN-1] = '\0';
        return temp;
    }
    if(str2.iNum[NUMLEN-2] == 'E' || iNum[NUMLEN-2] == 'E')
    {

        cout << "str.iNum[NUMLEN -1]= E"  << endl;

        temp.iNum[0] = 'E';
        temp.iNum[NUMLEN-2] = 'E';
        temp.iNum[NUMLEN-1] = '\0';
        return temp;
    }

    int i,pos,len,len2;
    char jin,k;
    len = strlen(iNum);
    len2 = strlen(str2.iNum);
    if(len2 >= len)
    {
    //    cout <<" len2 >= len" <<endl;
        int duo = len2 - len;
        jin = '\0';
        pos = len2 - 1;
        for(i=len - 1;i>=0;i--)
        {
            //cout << "pos=" << pos << endl;
            k = jin +str2.iNum[i+duo] - '0' + iNum[i]  - '0';
            if(k>='\12')  //8进制12等于十进制10
            {
                jin = '\1';
                k = k -'\12';
                temp.iNum[pos] = k +'0';
            }
            else
            {
                jin = '\0';
                temp.iNum[pos] = k +'0';
            }
          //  cout << pos << ":"<<str2.iNum[i+duo]<<":"<< iNum[i]<< ":"<<temp.iNum[pos]<<endl;
            pos = pos - 1;
        }
        for(i= len2 - len -1 ;i>=0;i-- )
        {
            k = str2.iNum[i] - '0' + jin;
            if(k>='\12')
            {
                k = k -'\12';
                temp.iNum[pos] = k +'0';
                jin = '\1';
            }
            else
            {
                temp.iNum[pos] = k +'0';
                jin = '\0';
            }
            pos = pos -1;
        }
        if(jin == '\1' )
        {
             if(len2 < NUMLEN-1)
            {

                for(i=len2-1;i>=0;i--)
                {
                    temp.iNum[i+1] = temp.iNum[i];
                }
                temp.iNum[0] = '1';
                temp.iNum[len2+1] = '\0';//99 199
            }
            else
            {
                temp.iNum[0] = 'E';
                if(NUMLEN>0)
                    temp.iNum[NUMLEN-2] = 'E';
                temp.iNum[NUMLEN-1] = '\0';

            }
        }
        else
        {
            temp.iNum[len2] = '\0';
        }
    //0123456789 len =10
    //     01234 len =5
    //pos=4
    }
    else //len2<len
    {
    //    cout <<"len2 < len" << endl;
        int duo = len - len2;
        jin = '\0';
        pos = len - 1;
        for(i=len2 - 1;i>=0;i--)
        {
        //cout << "pos=" << pos << endl;
            k = jin +iNum[i+duo] - '0' + str2.iNum[i]  - '0';
            if(k>='\12')  //8进制12等于十进制10
            {
                jin = '\1';
                k = k -'\12';
                temp.iNum[pos] = k +'0';
                //cout << "j"<< temp.iNum[pos];
            }
            else
            {
                jin = '\0';
                temp.iNum[pos] = k +'0';
            // cout << "w"<< temp.iNum[pos];
            }
            //cout << pos << ":"<<iNum[i+duo]<<":"<< str2.iNum[i]<< ":"<<temp.iNum[pos]<<endl;
            pos = pos - 1;
        }
        for(i= len - len2 -1 ;i>=0;i-- )
        {
            k = iNum[i] - '0' + jin;
            if(k>='\12')
            {
                k = k -'\12';
                temp.iNum[pos] = k +'0';
                jin = '\1';
            }
            else
            {
                temp.iNum[pos] = k +'0';
                jin = '\0';
            }
            pos = pos -1;
        }
        if(jin == '\1' )
        {
           if(len<NUMLEN-1)
            {
                for(i=len-1;i>=0;i--)
                {
                    temp.iNum[i+1] = temp.iNum[i];
                }
                temp.iNum[0] = '1';
                temp.iNum[len+1] = '\0';//99 199
            }
            else
            {
                temp.iNum[0] = 'E';
                if(NUMLEN>1)
                {
                temp.iNum[NUMLEN-2] = 'E';  //越界符号
                temp.iNum[NUMLEN-1] = '\0';

                }

            }
        }
        else
        {
            temp.iNum[len]='\0';
        }

    }
    return temp;
}

void setValue(char ch,int pos)
{
    iNum[pos] = ch;
}
char * getValue()
{
    return iNum;
}
char getValue(int pos)
{
    return iNum[pos];
}
void setch(char *ch)
{
    int i;
    for(i=0;i<(int)strlen(iNum);i++)
    {
        ch[i] = iNum[i];
    }
        ch[i]='\0';
}
    };

/*
void pai()  //from:https://blog.youkuaiyun.com/weixin_31080559/article/details/117145673?utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7EOPENSEARCH%7Edefault-2.no_search_link&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7EOPENSEARCH%7Edefault-2.no_search_link
{

//TDateTime t0 = Now();
clock_t start, finish;
 start = clock();
    double   duration;
const int ARRSIZE=10100, DISPCNT=10000; //定义数组大小，显示位数

char x[ARRSIZE], z[ARRSIZE]; //x[0] x[1] . x[2] x[3] x[4] .... x[ARRSIZE-1]

int a=1, b=3, c, d, Run=1, Cnt=0;

memset(x,0,ARRSIZE);

memset(z,0,ARRSIZE);

x[1] = 2;

z[1] = 2;

while(Run && (++Cnt<200000000))

{
//z*=a;

d = 0;

for(int i=ARRSIZE-1; i>0; i--)

{
c = z[i]*a + d;

z[i] = c % 10;

d = c / 10;

}

//z/=b;

d = 0;

for(int i=0; i<ARRSIZE-1; i++)


{
c = z[i]+d*10;

z[i] = c / b;

d = c % b;

}

//x+=z;

Run = 0;

for(int i=ARRSIZE-1; i>0; i--)

{
c = x[i] + z[i];

x[i] = c%10;

x[i-1] += c/10;

Run |= z[i];

}

a++;

b+=2;

}


string s;

printf("count %d\r\n", Cnt);

//s.cat_sprintf(_T("计算时间：%.3f 秒\r\n"), t);
printf("Pi=%d%d.", x[0], x[1]);

//for(int i=0; i<ARRSIZE-3;i++)
for(i=0; i<DISPCNT; i++){

{
if(i && ((i%100)==0))

s += ("\r\n");

s += (int)x[i+2];
printf("%d",x[i+2]);
}
printf("\n\n");
finish = clock();
duration = (double)(finish - start) / CLOCKS_PER_SEC;
printf( "%.3f seconds\n", duration );

return ;

}

*/
Bignum pi(int lenth); //计算π
int  compareBignum(const char*str1,const char*str2)
    {
    int ret;
    int i,len=strlen(str1);
    if(strlen(str1)==strlen(str2))
    {
        ret = 0;
        for(i=0;i<len;i++)
        {
            if(str1[i] > str2[i])
            {
                ret = 1;
                break;
            }
            else if(str1[i] < str2[i])
            {
              //  cout <<"str1=" << str1[i] <<"str2=" <<str2[i] <<endl;
                ret = -1;
                break;
            }
        }
    }
    else if(strlen(str1)>strlen(str2))
    {
        ret = 1;
    }
    else { ret = -1;}
    return ret;//ret=-1:str1<str2; =0:str1==str2;1:str1>str2
}
Bignum pi(int lenth)
{
    //pi/2=1+1/3+1/3*2/5+1/3*2/5*3/7+.....
    //pi=2+2/3+2/3*2/5+2/3*2/5*3/7+.....
    Bignum temp;
    Bignum pilen;
    Bignum temp0;//算过的分数
    Bignum temp1; //分子
    Bignum temp2;//分母
    char fentmp[NUMLEN];
    int i;
    int n;
    int res = 4;//多算几位，以保精确。
    cout << "pi........"<< endl;
    if(lenth > NUMLEN -1-res)
    {
        lenth = NUMLEN - 1;
    }
    else
    {
        lenth = lenth +  res;
    }
    temp.setValue('2',0);
    pilen.setValue('1',0);
    for(i=1;i<=lenth;i++)
    {
        pilen.setValue('0',i);
        temp.setValue('0',i);
    }
    pilen.setValue('\0',i);
    temp.setValue('\0',i);
    temp1.setValue('2',0);temp1.setValue('\0',1);
    temp2.setValue('3',0);temp2.setValue('\0',1);
  //  cout <<"pilen" << pilen.getValue() << " temp2=" << temp2.getValue() << endl;
    temp0 =pilen*temp1/temp2;
    temp = temp + temp0;
 //   cout <<"temp.getValue()="<<temp.getValue()<<endl;
    //n=2;
    for (n = 2; true; n++)
    {
        if((n % 100) == 0)
        {
            cout << "now precision is "<<n<<endl;
        }
        int k;
        itoa(n,fentmp,10);
   //     cout <<"fentmp="<<fentmp<<endl;
        for(k=0;k<(int)strlen(fentmp);k++)
        {
            temp1.setValue(fentmp[k],k) ;
        }
        temp1.setValue('\0',k);
        itoa(2*n+1,fentmp,10);
        for(k=0;k<(int)strlen(fentmp);k++)
        {
            temp2.setValue(fentmp[k],k);
        }
        temp2.setValue('\0',k);

        temp0 = temp0*temp1/temp2;
        temp = temp + temp0;
        if(temp0.getValue(0)=='0')
            break;
    }
    cout << "now precision is "<<n-1<<"  decimal digit:" << lenth - res<<endl;
  //  temp = temp + temp;
    return temp;
}
char* itoa(int num,char* str,int radix)  //整数转字符串
{/*索引表*/
    char index[]="0123456789ABCDEF";
    unsigned unum;/*中间变量*/
    int i=0,j,k;
    /*确定unum的值*/
    if(radix==10&&num<0)/*十进制负数*/
    {
        unum=(unsigned)-num;
        str[i++]='-';
    }
    else unum=(unsigned)num;/*其他情况*/
    /*转换*/
    do{
        str[i++]=index[unum%(unsigned)radix];
        unum/=radix;
       }while(unum);
    str[i]='\0';
    /*逆序*/
    if(str[0]=='-')
        k=1;/*十进制负数*/
    else
        k=0;

    for(j=k;j<=(i-1)/2;j++)
    {       char temp;
        temp=str[j];
        str[j]=str[i-1+k-j];
        str[i-1+k-j]=temp;
    }
    return str;
}
int main()
{
    char n1[NUMLEN];
    char op;
    char n2[NUMLEN];
    int k;
    //pi.........
Bignum pizhi;
//pizhi= pi(10,10);
for(k=20;k<100;k=k+1)
{
pizhi= pi(k);
char ret[NUMLEN];
pizhi.setch(ret);
int n,len2 = strlen(ret);
if(len2 > NUMLEN -2 )
    len2 = NUMLEN -2;
    if(len2>k+1)
        len2 = k+1;
for(n=len2;n>0;n--)
{
    ret[n+1]=ret[n];
}
ret[len2+1]='\0';
ret[1]='.';
cout << ret << endl;
}
cout <<"Test Calculations:" << endl;
while(true)
{
    printf("input the first number('-' exit)\n");
    scanf("%255s",n1);
    fflush(stdin);
    if(n1[0] == '-')
    {
        break;
    }
    Bignum temp1(n1);
    printf("input operator\n");
    scanf("%c",&op);
    printf("input the second number\n");
    scanf("%255s",n2);
    fflush(stdin);
    Bignum temp2(n2);
    Bignum temp3;

switch(op)
{
case '+':
    temp3 = temp1 + temp2;
    break;
case '-':
    temp3 = temp1 - temp2;
    break;
case '*':
    temp3 = temp1 * temp2;
    break;
case '/':
    temp3 = temp1 / temp2;
    break;
default:
    cout <<"input character is not +-*/"<<endl;
}
temp3.display();
}
    return 0;
}

codeblocks输出中文搞不定。vs就可以输出中文。

#define _CRT_SECURE_NO_WARNINGS
#include "stdafx.h"
#include <stdio.h>
#include <string.h>
using namespace std;
#define NUMLEN 1024   //must > 1
int compareBignum(const char*str1, const char*str2);
char* itoa(int num, char* str, int radix);  //整数转字符串
char * mymemset(char * dest, char value, size_t size);
class Bignum
{
	char iNum[NUMLEN];
public:
	Bignum()
	{
		mymemset(iNum, '\0', NUMLEN);
		//iNum[0] = '\0';
		//iNum[1] = '\0';
	}

	Bignum(char * num)
	{
		int i;
		for (i = 0; i< NUMLEN - 1; i++)
		{
			if (num[i] >= '0' && num[i] <= '9')
			{
				iNum[i] = num[i];
			}
			else if (num[i] == '\0')
			{
				iNum[i] = '\0';
				break;
			}
			else
			{
				iNum[0] = 'E';
				iNum[1] = '\0';
				break;
			}

		}
		//去掉前面的0
		if (iNum[0] == '0')
		{
			int num0 = 0;
			int len = strlen(iNum);
			for (i = 0; i<len; i++)
			{
				if (iNum[i] != '0')
					break;
				else
					num0++;
			}
			for (i = 0; i<len - num0; i++)
			{
				iNum[i] = iNum[i + num0];
			}
			iNum[i] = '\0';
			if (iNum[0] == '\0')
			{
				iNum[0] = '0';
				iNum[1] = '\0';
			}

		}
	}
public:
	Bignum operator +(const Bignum &str2) const {
		return jia(str2);
	}

public:
	Bignum operator *(const Bignum &str2) const {

		return chen(str2);
	}
public:
	Bignum operator /(const Bignum &str2) const {

		return chu(str2);
	}
public:
	Bignum operator -(const Bignum &str2) const{

		return jian(str2);
	}
	void display()
	{
		//  cout << "0="<<iNum[0] +'\12' << "  1="<< iNum[1] +'\12'<< endl;
		//cout << "this number is " << iNum << "   len=："<< len  << endl;
		printf("%s len=%d\n", iNum, strlen(iNum));
	}
public:
	bool operator ==(const Bignum &str2) const{
		unsigned int i;
		bool ret;
		if (strlen(iNum) == strlen(str2.iNum))
		{
			for (i = 0; i<strlen(iNum); i++)
			{
				if (iNum[i] != str2.iNum[i])
				{
					ret = false;
					break;
				}
				ret = true;

			}
		}
		return ret;
	}
public:
	bool operator > (const Bignum &str2) const{
		unsigned int i;
		bool ret;
		if (strlen(iNum) > strlen(str2.iNum))
			ret = true;
		else
		if (strlen(iNum) < strlen(str2.iNum))
		{
			ret = false;
		}
		else
		{
			for (i = 0; i<strlen(iNum); i++)
			{
				if (iNum[i] > str2.iNum[i])
				{
					ret = false;
					break;
				}
				ret = true;

			}
		}
		return ret;
	}
public:
	bool operator < (const Bignum &str2) const{
		unsigned int i;
		bool ret;
		if (strlen(iNum) < strlen(str2.iNum))
			ret = true;
		else
		if (strlen(iNum) > strlen(str2.iNum))
		{
			ret = false;
		}
		else
		{
			for (i = 0; i<strlen(iNum); i++)
			{
				if (iNum[i] < str2.iNum[i])
				{
					ret = false;
					break;
				}
				ret = true;

			}
		}
		return ret;
	}
	Bignum jian(const Bignum &str2) const
	{
		Bignum temp;
		if (iNum[0] == 'E' || str2.iNum[0] == 'E' || iNum[NUMLEN - 2] == 'E' || str2.iNum[NUMLEN - 2] == 'E')
		{
			temp.iNum[0] = 'E';
			temp.iNum[1] = '\0';
			temp.iNum[NUMLEN - 2] = 'E';
			temp.iNum[NUMLEN - 1] = '\0';
			return temp;
		}
		int duo;
		char k, jie;
		int pos;
		int len, len2, i;

		int comp = compareBignum(iNum, str2.iNum);
		if (comp == 1)
		{
			//  cout << "zhengshu" <<endl;
			jie = '\0';
			len = strlen(iNum);
			len2 = strlen(str2.iNum);
			duo = len - len2;
			pos = len - 1;
			for (i = len2 - 1; i >= 0; i--) //123456 123 6 3
			{
				if (str2.iNum[i] >(iNum[i + duo] - jie))
				{
					k = '\12' + iNum[i + duo] - str2.iNum[i] - jie; // '\12'+str1.iNum[i+duo] -'0' - (str2.iNum[i]-'0')
					jie = '\1';
				}
				else
				{
					k = iNum[i + duo] - str2.iNum[i] - jie;
					jie = '\0';
				}
				temp.iNum[pos] = k + '0';

				//   cout << pos << ":"<<str2.iNum[i]<<":"<< iNum[i+duo]<< ":"<<temp.iNum[pos]<<endl;
				pos = pos - 1;
			}//123456 123 6 3
			for (i = len - len2 - 1; i >= 0; i--)
			{
				if (iNum[i] == '0' && jie == '\1')
				{
					k = '\11';
					jie = '\1';
				}
				else
				{
					k = iNum[i] - '0' - jie;
					jie = '\0';
				}
				temp.iNum[pos] = k + '0';
				//      cout << pos << "*"<< iNum[i]<< ":"<<temp.iNum[pos]<<endl;

				pos = pos - 1;
			}
			int num0 = 0;//去前面的0
			for (i = 0; i<len; i++)
			{
				if (temp.iNum[i] == '0')
				{
					num0++;
				}
				else
				{
					break;
				}
			}
			if (num0>0)
			{
				for (i = num0; i<len; i++)
				{
					temp.iNum[i - num0] = temp.iNum[i];
				}
				temp.iNum[i - num0] = '\0';
			}
			else
			{
				temp.iNum[len] = '\0';
			}
		}
		else if (comp == -1) //先str2 - 本Bignum,再在前面加负号
		{
			//cout <<"fushu"<<endl;
			jie = '\0';
			len = strlen(iNum);
			len2 = strlen(str2.iNum);
			duo = len2 - len;
			pos = len2 - 1;
			for (i = len - 1; i >= 0; i--) //1777
			{                       // 999
				if (iNum[i] > (str2.iNum[i + duo] - jie))
				{
					k = '\12' + str2.iNum[i + duo] - iNum[i] - jie; // '\12'+str1.iNum[i+duo] -'0' - (str2.iNum[i]-'0')
					jie = '\1';
				}
				else
				{
					k = str2.iNum[i + duo] - iNum[i] - jie;
					jie = '\0';
				}
				temp.iNum[pos] = k + '0';

				// cout << pos << ":"<<str2.iNum[i+duo]<<":"<< iNum[i]<< ":"<<temp.iNum[pos]<<endl;
				pos = pos - 1;
			}
			for (i = len2 - len - 1; i >= 0; i--) //999 3 10011
			{
				if (str2.iNum[i] == '0' && jie == '\1')
				{
					k = '\11';  //八进制11等于十进制9
					jie = '\1';
				}
				else
				{
					k = str2.iNum[i] - '0' - jie;
					jie = '\0';
				}
				temp.iNum[pos] = k + '0';
				//  cout << pos << ":;"<<str2.iNum[i]<<":"<<temp.iNum[pos]<<endl;

				pos = pos - 1;
			}
			int num0 = 0;//去前面的0
			for (i = 0; i<len2; i++)
			{
				if (temp.iNum[i] == '0')
				{
					num0++;
				}
				else
				{
					break;
				}
			}
			//000123456 len2=9 num0=3 -123456
			if (num0>1)
			{
				for (i = num0; i<len2; i++)
				{
					temp.iNum[i - num0 + 1] = temp.iNum[i];
				}
				temp.iNum[0] = '-';
				temp.iNum[len2 - num0 + 1] = '\0';
			}
			else if (num0 == 1)
			{
				//cout << -1 << endl;
				temp.iNum[0] = '-';
				temp.iNum[len2] = '\0';
			}
			else
			{
				for (i = len2; i>0; i--)
				{
					temp.iNum[i] = temp.iNum[i - 1];
				}
				if (len2 <NUMLEN - 2)
				{
					temp.iNum[0] = '-';
					temp.iNum[len2 + 1] = '\0';
				}
				else
				{
					temp.iNum[0] = '-';
					temp.iNum[NUMLEN - 2] = 'E';
					temp.iNum[NUMLEN - 1] = '\0';
				}

			}

		}
		else
		{
			temp.iNum[0] = '0';
			temp.iNum[1] = '\0';
		}
		return temp;
	}

	Bignum chen(const Bignum &str2) const //两个数大于等于0
	{
		/* Bignum temp; //返回值
		Bignum temp2; //str2 的副本
		Bignum temp3;  //本值
		Bignum temp4("1");
		Bignum temp5;
		unsigned int i;
		if(iNum[0] == 'E' || str2.iNum[0] == 'E')
		{
		temp.iNum[0] = 'E';
		temp.iNum[1] = '\0';
		return temp;
		}
		if(str2.iNum[0]== '0' && str2.iNum[1]== '\0')
		{
		temp.iNum[0] = '0';
		temp.iNum[1] = '\0';
		return temp;
		}
		for(i=0;i<=strlen(iNum);i++)
		{
		temp.iNum[i] = iNum[i];
		}

		if(str2.iNum[0]== '1' && str2.iNum[1]== '\0')
		{
		return temp;
		}

		temp3 = temp;

		for(i=0;i<=strlen(str2.iNum);i++)
		{
		temp2.iNum[i] = str2.iNum[i];
		}

		while(temp2.iNum[0]!='1' || temp2.iNum[1]!='\0')
		{
		temp = temp + temp3;
		temp2 = temp2 - temp4;

		}*/

		//模拟乘法步骤
		int  i, k;
		int j;
		int e = 0;  //指数代表位数
		Bignum temp0;//本数
		Bignum temp("0");  //返回值
		Bignum temp2;  //中间值
		//    cout <<"start1= " << str2.iNum<< endl;
		if (iNum[0] == 'E' || iNum[NUMLEN - 2] == 'E' || str2.iNum[0] == 'E' || str2.iNum[NUMLEN - 2] == 'E')
		{
			temp.iNum[0] = 'E';
			temp.iNum[1] = '\0';
			return temp;
		}
		//     cout <<"start2= " << str2.iNum<< endl;

		for (i = 0; i<(int)strlen(iNum); i++)
		{
			temp0.iNum[i] = iNum[i];
		}
		//     cout <<"start3= " << str2.iNum<< endl;

		temp0.iNum[i] = '\0';
		//    cout <<"start4 for temp0=" << temp0.iNum << "str2="<< str2.iNum<<endl;

		for (i = strlen(str2.iNum) - 1; i >= 0; i--)
		{
			//中间值归零
			temp2.iNum[0] = '0';
			temp2.iNum[1] = '\0';
			if (str2.iNum[i] == '0')
			{
				//        cout <<"start 0  " << i <<endl;

				temp2.iNum[0] = '0';
				temp2.iNum[1] = '\0';
			}
			else
			if (str2.iNum[i] == '1')
			{
				//        cout <<"start 1  " << i <<endl;

				temp2 = temp0;
			}
			else
			if (str2.iNum[i] == '2')
			{
				//     cout <<"start 2  " << i <<endl;
				temp2 = temp0 + temp0;
			}
			else
			if (str2.iNum[i] == '3')
			{
				//     cout <<"start 3  " << i <<endl;
				temp2 = temp0 + temp0 + temp0;
			}
			else
			if (str2.iNum[i] == '4')
			{
				//    cout <<"start 4  " << i <<endl;
				temp2 = temp0 + temp0;
				temp2 = temp2 + temp2;
			}
			else
			if (str2.iNum[i] == '5')
			{
				//     cout <<"start 5  " << i <<endl;
				temp2 = temp0 + temp0;
				temp2 = temp2 + temp2;
				temp2 = temp2 + temp0;
			}
			else
			if (str2.iNum[i] == '6')
			{
				//   cout <<"start 6  " << i <<endl;
				temp2 = temp0 + temp0;
				temp2 = temp2 + temp0;
				temp2 = temp2 + temp2;
			}
			else
			if (str2.iNum[i] == '7')
			{
				//   cout <<"start 7  "<< i  <<endl;
				temp2 = temp0 + temp0;
				temp2 = temp2 + temp0;
				temp2 = temp2 + temp2;
				temp2 = temp2 + temp0;
			}
			else
			if (str2.iNum[i] == '8')
			{
				// cout <<"start 8  " << i <<endl;
				temp2 = temp0 + temp0;
				temp2 = temp2 + temp2;
				temp2 = temp2 + temp2;
			}
			else
			if (str2.iNum[i] == '9')
			{
				//  cout <<"start 9  " << i <<endl;
				temp2 = temp0 + temp0;
				temp2 = temp2 + temp2;
				temp2 = temp2 + temp2;
				temp2 = temp2 + temp0;
			}
			//   cout <<"start e " << temp2.iNum << endl;
			if (e>0 && temp2.iNum[0] != '0')
			{
				if (temp2.iNum[0] != 'E' && temp2.iNum[NUMLEN - 2] != 'E')
				{
					k = strlen(temp2.iNum);
					//          cout <<" k=" << k <<endl;
					if (e + k<NUMLEN - 2)
					{
						for (j = 0; j < e; j++)
						{
							temp2.iNum[k + j] = '0';

						}
						temp2.iNum[k + j] = '\0';
					}
					else
					{
						//  cout << "e="<<e<<" k="<<k<<endl;
						temp2.iNum[NUMLEN - 2] = 'E';
						temp2.iNum[0] = 'E';
						temp2.iNum[NUMLEN - 1] = '\0';

					}
				}
			}
			if (temp2.iNum[NUMLEN - 2] == 'E')
			{
				//越界了
				temp.iNum[NUMLEN - 2] = 'E';
				temp.iNum[0] = 'E';
				temp.iNum[NUMLEN - 1] = '\0';
				// cout << "temp2=" << temp2.iNum << "len="<<strlen(temp2.iNum) << endl;
				break;
			}
			else
			{
				temp = temp + temp2;
				if (temp.iNum[NUMLEN - 2] == 'E')
				{
					//temp.iNum[NUMLEN-1]='E';
					temp.iNum[0] = 'E';
					temp.iNum[NUMLEN - 1] = '\0';
					//  cout <<"temp ="<< temp.iNum <<endl;
					break;
				}
			}
			//   cout << "temp2=" << temp2.iNum << "  temp=" << temp.iNum <<"  e="<<e << endl;
			e++;


		}


		return temp;

	}

	Bignum chu(const Bignum &str2) const //两个数大于0
	{
		Bignum temp;//返回值
		Bignum temp0("5"); //试验值
		Bignum temp1;  //截取被除数长度
		Bignum yutemp; //余数
		int k;
		int pos = 0;//得数位置
		int pos1;   //原被除数被计算位置
		int len = (int)strlen(iNum);
		int len2 = (int)strlen(str2.iNum);
		int len1;//temp1.iNum长度
		//   cout <<"iNum="<<iNum<<" str2="<< str2.iNum << endl;
		if (len < len2)

		{
			temp.iNum[0] = '0';
			temp.iNum[1] = '\0';
			return temp;
		}
		for (k = 0; k<len2; k++)
		{
			temp1.iNum[k] = iNum[k];
		}
		temp1.iNum[len2] = '\0';//这时k=len2。
		if (compareBignum(temp1.iNum, str2.iNum) == -1) //小于被除数，就算到下一位
		{
			if (len2 < len)   //012345
			{
				temp1.iNum[len2] = iNum[len2]; //这时k=len2。
				temp1.iNum[len2 + 1] = '\0';
				pos1 = len2;

			}
			else //len==len2,没有下一位
			{
				temp.iNum[0] = '0';
				temp.iNum[1] = '\0';
				return  temp;
			}
		}
		else
		{
			pos1 = len2 - 1; //这时k=len2。pos1从0算起，所以减1.
		}

		while (true)
		{

			//cout << "temp1=" << temp1.iNum << "str2=" << str2.iNum <<"yutemp="<<yutemp.iNum<< "temp=" << temp.iNum<<endl;
			while (true)
			{
				temp0.iNum[0] = '5';
				yutemp = temp1 - str2 * temp0;
				if (yutemp.iNum[0] == '-')  //5不足
				{
					temp0.iNum[0] = '3';
					yutemp = temp1 - str2 * temp0;
					if (yutemp.iNum[0] == '-')   //3不足
					{
						temp0.iNum[0] = '2';
						yutemp = temp1 - str2 * temp0;
						if (yutemp.iNum[0] == '-') //2不足
						{
							yutemp = temp1 - str2;
							temp.iNum[pos] = '1';
							temp.iNum[pos + 1] = '\0';
							pos = pos + 1;
							break;
						}
						else  //2有余
						{
							temp.iNum[pos] = '2';
							temp.iNum[pos + 1] = '\0';
							pos = pos + 1;
							break;

						}
					}
					else        //3足 5不足
					{
						temp0.iNum[0] = '4';
						yutemp = temp1 - str2 * temp0;
						if (yutemp.iNum[0] == '-') //4不足
						{
							temp0.iNum[0] = '3';
							yutemp = temp1 - str2 * temp0;
							temp.iNum[pos] = '3';
							temp.iNum[pos + 1] = '\0';
							pos = pos + 1;
							break;
						}
						else//4有余
						{
							temp.iNum[pos] = '4';
							temp.iNum[pos + 1] = '\0';
							pos = pos + 1;
							break;
						}
					}
				}
				else  //5足
				{
					temp0.iNum[0] = '7';
					yutemp = temp1 - str2 * temp0;
					if (yutemp.iNum[0] == '-')   //7不足
					{
						temp0.iNum[0] = '6';
						yutemp = temp1 - str2 * temp0;
						if (yutemp.iNum[0] == '-') //6不足
						{
							temp0.iNum[0] = '5';
							yutemp = temp1 - str2 * temp0;
							temp.iNum[pos] = '5';
							temp.iNum[pos + 1] = '\0';
							pos = pos + 1;
							break;
						}
						else  //6有余
						{
							temp.iNum[pos] = '6';
							temp.iNum[pos + 1] = '\0';
							pos = pos + 1;
							break;

						}
					}
					else        //7足
					{
						temp0.iNum[0] = '8';
						yutemp = temp1 - str2 * temp0;
						if (yutemp.iNum[0] == '-') //8不足
						{
							temp0.iNum[0] = '7';
							yutemp = temp1 - str2 * temp0;
							temp.iNum[pos] = '7';
							temp.iNum[pos + 1] = '\0';
							pos = pos + 1;
							break;
						}
						else//8有余
						{
							temp0.iNum[0] = '9';
							yutemp = temp1 - str2 * temp0;
							if (yutemp.iNum[0] == '-') //9不足
							{
								temp0.iNum[0] = '8';
								yutemp = temp1 - str2 * temp0;
								temp.iNum[pos] = '8';
								temp.iNum[pos + 1] = '\0';
								pos = pos + 1;
								break;
							}
							else //9足
							{
								//  yutemp = temp1 - str2 * temp0;
								temp.iNum[pos] = '9';
								temp.iNum[pos + 1] = '\0';
								pos = pos + 1;
								break;
							}
						}
					}
				}

			}

			//重新算被除数
			if (pos1 == len - 1)
			{
				// cout << "pos1 + len2 > len" << " pos1 =" << pos1 <<" len2=" <<len2 << " len=" <<len<<"pos="<< pos<< endl;
				//cout <<"2pos1 == len -1 ret=" << temp.iNum << endl;
				return temp;
			}
			if (yutemp.iNum[0] != '0')//余数不为0
			{
				for (k = 0; k<(int)strlen(yutemp.iNum); k++)
				{
					//余数作为被除数的一部分
					temp1.iNum[k] = yutemp.iNum[k];
				}
				len1 = strlen(temp1.iNum);
				pos1 = pos1 + 1;
				temp1.iNum[k] = iNum[pos1];
				temp1.iNum[k + 1] = '\0';

				while (compareBignum(temp1.iNum, str2.iNum) == -1) //小于被除数，就算到下一位
				{
					if (pos1 == len - 1)  //没有下一位，等于0。
					{
						temp.iNum[pos] = '0';
						temp.iNum[pos + 1] = '\0';
						pos = pos + 1;
						//       cout << "pos1 == len -1" << endl;
						// cout <<"pos1 == len -1  ret="<<temp.iNum<<endl;
						return temp;
					}
					else //有下一位，这个位置结果是0。
					{
						temp.iNum[pos] = '0';
						temp.iNum[pos + 1] = '\0';
						pos = pos + 1;

						pos1 = pos1 + 1;
						k = k + 1;
						temp1.iNum[k] = iNum[pos1];
						temp1.iNum[k + 1] = '\0';
					}
				}
			}
			else  //余数是0  1110  11 100
			{
				//    cout << "temp="<<temp.iNum << " len=" << len <<" pos1="<< pos1 <<" temp1="<<temp1.iNum<<endl;
				//如果当前值为0
				pos1 = pos1 + 1;
				while (iNum[pos1] == '0')
				{
					temp.iNum[pos] = '0';
					temp.iNum[pos + 1] = '\0';
					pos1 = pos1 + 1;
					pos = pos + 1;
				}
				//   cout << "pos1=" <<pos1  <<"len=" <<len << endl;
				if (pos1 == len)
				{
					//  cout <<"1pos1 ==  len ret="<<temp.iNum<<endl;
					return temp;
				}

				for (k = 0; k<len2 - 1; k++)
				{
					temp1.iNum[k] = iNum[pos1];
					temp1.iNum[k + 1] = '\0';
					pos1 = pos1 + 1;
					temp.iNum[pos] = '0';
					temp.iNum[pos + 1] = '\0';
					pos = pos + 1;
					if (pos1 == len)
					{
						//  cout <<"pos1 ==  len ret="<<temp.iNum<<endl;

						return temp;
					}
				}
				//    cout << "temp1.iNum=" <<temp1.iNum << " pos="<<pos<<endl;
				temp1.iNum[k] = iNum[pos1];
				temp1.iNum[k + 1] = '\0';
				pos1 = pos1 + 1;

				if (compareBignum(temp1.iNum, str2.iNum) == -1)
				{
					//      cout <<"compareBignum(temp1.iNum,str2.iNum)==-1"<<endl;
					if (pos1 == len)
					{
						temp.iNum[pos] = '0';
						temp.iNum[pos + 1] = '\0';
						return temp;
					}
					else   // 1110111011  11
					{
						temp.iNum[pos] = '0';
						temp.iNum[pos + 1] = '\0';
						pos = pos + 1;

						k = k + 1;
						temp1.iNum[k] = iNum[pos1];
						temp1.iNum[k + 1] = '\0';
						pos1 = pos1 + 1;

					}
				}
				pos1 = pos1 - 1; //因循环，被加了1.



			}


		} //while
		// temp.iNum[pos] = '\0';
		//   cout <<"ret="<<temp.iNum<<endl;
		return temp;

	}

	Bignum jia(const Bignum &str2) const
	{
		Bignum temp;
		if (iNum[0] == 'E' || str2.iNum[0] == 'E')
		{
			printf("不是数据,0=E\n");
			temp.iNum[0] = 'E';
			temp.iNum[1] = '\0';
			temp.iNum[NUMLEN - 2] = 'E';
			temp.iNum[NUMLEN - 1] = '\0';
			return temp;
		}
		if (str2.iNum[NUMLEN - 2] == 'E' || iNum[NUMLEN - 2] == 'E')
		{
			printf("不是数据,末尾=E\n");

			temp.iNum[0] = 'E';
			temp.iNum[NUMLEN - 2] = 'E';
			temp.iNum[NUMLEN - 1] = '\0';
			return temp;
		}

		int i, pos, len, len2;
		char jin, k;
		len = strlen(iNum);
		len2 = strlen(str2.iNum);
		if (len2 >= len)
		{
			//    cout <<" len2 >= len" <<endl;
			int duo = len2 - len;
			jin = '\0';
			pos = len2 - 1;
			for (i = len - 1; i >= 0; i--)
			{
				//cout << "pos=" << pos << endl;
				k = jin + str2.iNum[i + duo] - '0' + iNum[i] - '0';
				if (k >= '\12')  //8进制12等于十进制10
				{
					jin = '\1';
					k = k - '\12';
					temp.iNum[pos] = k + '0';
				}
				else
				{
					jin = '\0';
					temp.iNum[pos] = k + '0';
				}
				//  cout << pos << ":"<<str2.iNum[i+duo]<<":"<< iNum[i]<< ":"<<temp.iNum[pos]<<endl;
				pos = pos - 1;
			}
			for (i = len2 - len - 1; i >= 0; i--)
			{
				k = str2.iNum[i] - '0' + jin;
				if (k >= '\12')
				{
					k = k - '\12';
					temp.iNum[pos] = k + '0';
					jin = '\1';
				}
				else
				{
					temp.iNum[pos] = k + '0';
					jin = '\0';
				}
				pos = pos - 1;
			}
			if (jin == '\1')
			{
				if (len2 < NUMLEN - 1)
				{

					for (i = len2 - 1; i >= 0; i--)
					{
						temp.iNum[i + 1] = temp.iNum[i];
					}
					temp.iNum[0] = '1';
					temp.iNum[len2 + 1] = '\0';//99 199
				}
				else
				{
					temp.iNum[0] = 'E';
					if (NUMLEN>0)
						temp.iNum[NUMLEN - 2] = 'E';
					temp.iNum[NUMLEN - 1] = '\0';

				}
			}
			else
			{
				temp.iNum[len2] = '\0';
			}
			//0123456789 len =10
			//     01234 len =5
			//pos=4
		}
		else //len2<len
		{
			//    cout <<"len2 < len" << endl;
			int duo = len - len2;
			jin = '\0';
			pos = len - 1;
			for (i = len2 - 1; i >= 0; i--)
			{
				//cout << "pos=" << pos << endl;
				k = jin + iNum[i + duo] - '0' + str2.iNum[i] - '0';
				if (k >= '\12')  //8进制12等于十进制10
				{
					jin = '\1';
					k = k - '\12';
					temp.iNum[pos] = k + '0';
					//cout << "j"<< temp.iNum[pos];
				}
				else
				{
					jin = '\0';
					temp.iNum[pos] = k + '0';
					// cout << "w"<< temp.iNum[pos];
				}
				//cout << pos << ":"<<iNum[i+duo]<<":"<< str2.iNum[i]<< ":"<<temp.iNum[pos]<<endl;
				pos = pos - 1;
			}
			for (i = len - len2 - 1; i >= 0; i--)
			{
				k = iNum[i] - '0' + jin;
				if (k >= '\12')
				{
					k = k - '\12';
					temp.iNum[pos] = k + '0';
					jin = '\1';
				}
				else
				{
					temp.iNum[pos] = k + '0';
					jin = '\0';
				}
				pos = pos - 1;
			}
			if (jin == '\1')
			{
				if (len<NUMLEN - 1)
				{
					for (i = len - 1; i >= 0; i--)
					{
						temp.iNum[i + 1] = temp.iNum[i];
					}
					temp.iNum[0] = '1';
					temp.iNum[len + 1] = '\0';//99 199
				}
				else
				{
					temp.iNum[0] = 'E';
					if (NUMLEN>1)
					{
						temp.iNum[NUMLEN - 2] = 'E';  //越界符号
						temp.iNum[NUMLEN - 1] = '\0';

					}

				}
			}
			else
			{
				temp.iNum[len] = '\0';
			}

		}
		return temp;
	}

	void setValue(char ch, int pos)
	{
		iNum[pos] = ch;
	}
	char * getValue()  //codeblocks 可以调用，vs不可以
	{
		return iNum;
	}
	void getValue(char *ch)  //vs要这个获得数据。
	{
		int i;
		for (i = 0; i<(int)strlen(iNum); i++)
		{
			ch[i] = iNum[i];
		}
		ch[i] = '\0';
	}
	char getValue(int pos)  //vs要这个获得数据。
	{
		return iNum[pos];
	}

};
char * mymemset(char * dest, char value, size_t size)
{
	size_t i;
	for (i = 0; i < size; i++)
	{
		dest[i] = value;
	}
	return dest;
}
Bignum pi(int lenth); //计算π
int  compareBignum(const char*str1, const char*str2)
{
	int ret;
	int i, len = strlen(str1);
	if (strlen(str1) == strlen(str2))
	{
		ret = 0;
		for (i = 0; i<len; i++)
		{
			if (str1[i] > str2[i])
			{
				ret = 1;
				break;
			}
			else if (str1[i] < str2[i])
			{
				//  cout <<"str1=" << str1[i] <<"str2=" <<str2[i] <<endl;
				ret = -1;
				break;
			}
		}
	}
	else if (strlen(str1)>strlen(str2))
	{
		ret = 1;
	}
	else { ret = -1; }
	return ret;//ret=-1:str1<str2; =0:str1==str2;1:str1>str2
}
Bignum pi(int lenth)
{
	//pi/2=1+1/3+1/3*2/5+1/3*2/5*3/7+.....
	//pi=2+2/3+2/3*2/5+2/3*2/5*3/7+.....
	Bignum temp;
	Bignum pilen;
	Bignum temp0;//算过的分数
	Bignum temp1; //分子
	Bignum temp2;//分母
	char fentmp[NUMLEN];
	int i;
	int n;
	int res = 4;//多算几位，以保精确。
	printf("pi值计算中......\n");
	if (lenth > NUMLEN - 2 - res)
	{
		lenth = NUMLEN - 2;
	}
	else
	{
		lenth = lenth + res;
	}
	temp.setValue('2', 0);
	pilen.setValue('1', 0);
	for (i = 1; i<=lenth; i++)
	{
		pilen.setValue('0', i);
		temp.setValue('0', i);
	}
	pilen.setValue('\0', i);
	temp.setValue('\0', i);
	temp1.setValue('2', 0); temp1.setValue('\0', 1);
	temp2.setValue('3', 0); temp2.setValue('\0', 1);
	temp0 = pilen*temp1 / temp2;
	temp = temp + temp0;
	for (n = 2; true; n++)
	{
		int k;
		if (n % 100 == 0)
		{
			printf("已经达到精度%d\n",n);
		}
		itoa(n, fentmp, 10);
		for (k = 0; k<(int)strlen(fentmp); k++)
		{
			temp1.setValue(fentmp[k], k);
		}
		temp1.setValue('\0', k);
		itoa(2 * n + 1, fentmp, 10);
		for (k = 0; k<(int)strlen(fentmp); k++)
		{
			temp2.setValue(fentmp[k], k);
		}
		temp2.setValue('\0', k);
		temp0 = temp0*temp1 / temp2;
		temp = temp + temp0;
		if (temp0.getValue(0) == '0')
			break;
	}
	printf("已经达到精度%d，小数位数%d。\n", n-1,lenth - res);
	return temp;
}
char* itoa(int num, char* str, int radix)  //整数转字符串
{/*索引表*/
	char index[] = "0123456789ABCDEF";
	unsigned unum;/*中间变量*/
	int i = 0, j, k;
	/*确定unum的值*/
	if (radix == 10 && num<0)/*十进制负数*/
	{
		unum = (unsigned)-num;
		str[i++] = '-';
	}
	else unum = (unsigned)num;/*其他情况*/
	/*转换*/
	do{
		str[i++] = index[unum % (unsigned)radix];
		unum /= radix;
	} while (unum);
	str[i] = '\0';
	/*逆序*/
	if (str[0] == '-')
		k = 1;/*十进制负数*/
	else
		k = 0;

	for (j = k; j <= (i - 1) / 2; j++)
	{
		char temp;
		temp = str[j];
		str[j] = str[i - 1 + k - j];
		str[i - 1 + k - j] = temp;
	}
	return str;
}
int main()
{
	char n1[NUMLEN];
	char op;
	char n2[NUMLEN];
	//pi.........
	Bignum pizhi;
	int k = 10000;
	pizhi = pi(k);//再多的精度结果一样，比这个少的精度结果不一样。
//	pizhi = pi(10, 10);//再多的精度结果一样，比这个少的精度结果不一样。
	char ret[NUMLEN];
	pizhi.getValue(ret);
	int n, len2 = strlen(ret);
	if (len2 > NUMLEN - 2)
		len2 = NUMLEN - 2;
	if (len2>k + 1)
		len2 = k + 1;
	for (n = len2; n>0; n--)
	{
		ret[n + 1] = ret[n];
	}
	ret[len2 + 1] = '\0';
	ret[1] = '.';
	printf("%s\n", ret);
	printf("\n\n\n测试计算：");
	while (true)
	{
		printf("输入第一个数('-'退出)：\n");
		scanf_s("%255s", n1,NUMLEN);
		fflush(stdin);
		if (n1[0] == '-')
		{
			break;
		}
		Bignum temp1(n1);
		printf("输入运算符（+-*/）：\n");
		scanf_s("%c", &op,1);
		printf("input the second number\n");
		scanf_s("%255s", n2,256);
		fflush(stdin);
		Bignum temp2(n2);
		Bignum temp3;

		switch (op)
		{
		case '+':
			temp3 = temp1 + temp2;
			break;
		case '-':
			temp3 = temp1 - temp2;
			break;
		case '*':
			temp3 = temp1 * temp2;
			break;
		case '/':
			temp3 = temp1 / temp2;
			break;
		default:
			printf("不是+-*/。");
		}
		temp3.display();
	}
	return 0;
}

可以设置NUMLEN的数值，适应准备的运算，以节省内存。

c语言计算pi后1000位,计算圆周率 Pi (π)值, 精确到小数点后 10000 位
weixin_42505792的博客
05-19 4800
大家都知道π=3.1415926……无穷多位, 历史上很多人都在计算这个数, 一直认为是一个非常复杂的问题。现在有了电脑, 这个问题就简单了。电脑可以利用级数计算出很多高精度的值, 有关级数的问题请参考《高等数学》,以下是比较有名的有关π的级数:其中有些计算起来很复杂, 我们可以选用第三个, 比较简单, 并且收敛的非常快。因为计算π值, 而这个公式是计算π/2的, 我们把它变形:π = 2 + 2...
大数四则运算的C++实现
We_are_family678的博客
04-04 508
大数四则运算的C++实现[摘要] 大数运算不仅仅运用在密码学中，还运用在一些物理学研究、生物学，化学等科目中。大数运算，意味着参加的值和计算结果通常是以上百位数，上千位数以及更大长度之间的整数运算。例如大家所熟知圆周率π的值，在一般的数值计算中用到圆周率的不须要多大的精度，但在计算一些星球或是星系上的体积面积时便显的误差很大了，这就要求π值计算的精度达到几百万位甚至更高，才能缩小误差。人工计算是远...
C++计算高精度圆周率
02-11
C/C++
C++实现高精度除法（附带源码）
最新发布
欢迎来到我的博客！这里是一个专注于计算机技术的分享平台，涵盖编程开发、算法研究、系统架构、软件工程等多个领域。无论你是初学者还是资深开发者，都能在这里找到有价值的内容。
01-26 680
高精度除法是计算机数学运算中的一种重要技术，能够处理普通数据类型（如 int 或 double）无法精确表达的大数字计算问题。特别是在科学计算、密码学等领域，高精度运算可以避免因为溢出或舍入误差而导致的错误。
c++语言计算圆周率,求C++计算圆周率小数点后10000位的程序，感谢。不知道怎么实现大数...
weixin_32285357的博客
05-23 795
该楼层疑似违规已被系统折叠隐藏此楼查看此楼6407655904 2909945681 5065265305 3718294127 03369313785178609040 7086671149 6558343434 7693385781 71138645587367812301 4587687126 6034891390 9562009939 36103102916161528813 84379...
python作业
diaomeijiao3430的博客
10-07 232
代码： from time import clock clock() N=1010 WIDTH=N-10 a,b,c,d,i,run,cnt,cntMAX=1,3,0,0,0,1,1,1000000 x,z=[],[] for i in range(N): x.append(0) z.append(0) x[1]=2 z[1]=2 while...
C++ 随机化算法求pi(保留小数位1000位以上）
JulianBrandt的博客
06-05 2142
C++ 随机化算法求pi(保留小数位1000位以上） #include"标头.h" #include<iostream> #include<random> #include<vector> using namespace std; // 圆周率求到 10^-10 default_random_engine e; uniform_real_distribut...
高精度高性能PI值计算程序设计和验证
zhangfuliang93的博客
06-05 2313
一、PI的计算方法 程序中实现了4类14种PI的计算方法，每种方法都实测过，确保计算结果的准确性，所有方法至少试验过1~10万位的求解，输出有效数字完全相同，并与y-cruncher等标准程序输出结果进行了对照。 Method 1-7为类Machin公式，也就是反正切函数的Taylor级数；程序中实现了传统累加法和P2B3模型法（P2B3模型的含义在后面章节有专门介绍） Method 10-16为类BBP级数，包括标准BBP级数、Fabrice Bellard级数，程序实现了传统累加法和P2B3/BB
儒略历由来 / 儒略日计算公式 / 历法演化
u013669912的博客
07-14 1万+
……
【浮点运算优化术】：基于IEEE-754标准的效率提升攻略
!... # 摘要 浮点运算在现代计算领域扮演着核心角色，尽管它为各种科学和...IEEE-754标准为浮点运算提供了基础，规定了数据的内部表示和四则运算规则。在编程实践中，语言和硬件的特性对浮点运算的效率和优化至关重要。本
中职c语言多选题及答案,国二c语言题库选择题答案
weixin_32950005的博客
05-17 1633
第一部分C基础部分及顺序结构参考答案及解析1、【答案】A【解析】C语言被称为“高级语言”是因为它用接近英语国家的自然语言和数学语言作为表达形式，使人们学习和操作起来感到十分方便，相对于其他的高级语言来说，C语言有它自身的优缺点，但却是用的最广泛的语言。由于它可以直接控制计算机硬件，因此其编写的程序运行效率较高。用C语言编写的程序称作C语言源程序，C源程序不能直接执行。C语言的每条可执行语句最终将被...
计算精确到4000位的圆周率 VC++6
01-05
30多行的代码C++计算精确到4000位的圆周率, 计算位数可自行修改， 代码非常短小精干，值得参考，VC++6编译通过
圆周率计算 3000位 pi的计算 VC++ C++代码
08-07
圆周率计算 3000位 pi的计算 VC++ C++代码 圆周率计算 3000位 pi的计算 VC++ C++代码
C语言程序设计圆周率,如何设计C语言程序输出圆周率小数点后的1000位？请大侠出手啊。...
weixin_33581743的博客
05-18 262
该楼层疑似违规已被系统折叠隐藏此楼查看此楼3.14159265358979323846264338327950288419716939937510582097494459230781640628620899862803482534211706798214808651328230664709384460955058223172535940812848111745028410270193852110...
计算圆周率的C程序
weixin_34315665的博客
09-28 1485
这是很早以前用C语言写的一个计算圆周率的程序,  算法是用泰勒公式计算反正切值。在命令行不跟参数执行该程序则使用Gauss公式计算前1000位圆周率的值，如果带一个命令行参数，则该值为要计算的位数。如果还有第二个命令行参数，则使用Stomer公式计算，可作为验算。因为该程序只涉及到纯数学计算，可以在Linux、Unix、Windows等操作系统下编译并运行。当时写这个程序时，int是2个字节的，现...
计算圆周率的C++程序(30000位)
热门推荐
wanchuanhua的专栏
11-09 1万+
<br />//计算圆周率的C++程序(30000位)<br />#include <stdlib.h><br />#include <math.h><br />#include <memory.h><br />#define N 10000<br />//using namespace std; <br />void mult(int *a,int b,int *s)<br />{ for(int i=N,c=0; i>=0; i--)<br /> { int y=a[i]*b+c;<br />  c=y
【大整数四则运算】
weixin_30468137的博客
01-04 422
定义并实现超长整数类double long，要求如下： 64位数据长度，有符号 支持＋、－、＊、／运算 支持＋＝、－＝、／＝运算 支持cin>>和cout<<操作 首先，我们的运算对象是大整数并且要支持cout<<和cin>>操作，数组和链表是可选择项。在这里我们用数组。数组有int型和char型，选哪个好呢？只能选cha...
蒙特卡洛方法_C++｜蒙特卡洛方法和微分法求圆周率PI值
weixin_39683769的博客
11-21 885
电脑的特点在于速度快，记忆好，最擅长做机械化的重复工作，用暴力的方法来近似pi值可以利用蒙特卡洛方法或微分法来计算。1 蒙特卡洛方法和微分法求π值如上图所示：对于单元圆的面积：πr^2=π(单位圆的半径为1)正方形的面积：11/4单元圆与正方形的面积的比值=4/π如果随机产生一个0－1内的数，其落在1/4单元圆内的概率与落在正方形内的概率就是两个图形的面积之比，随机数越多，越真实接近。落在正方形内...
c语言1000万位圆周率,如何设计C语言程序输出圆周率小数点后的1000位？请大侠出手啊。...
weixin_39972567的博客
05-20 204
该楼层疑似违规已被系统折叠隐藏此楼查看此楼3.14159265358979323846264338327950288419716939937510582097494459230781640628620899862803482534211706798214808651328230664709384460955058223172535940812848111745028410270193852110...
评论
添加红包

请填写红包祝福语或标题

个

红包个数最小为10个

元

红包金额最低5元

当前余额3.43元 前往充值 >
需支付：10.00元
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付元
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明：

1.余额是钱包充值的虚拟货币，按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载，可以购买VIP、付费专栏及课程。

余额充值