第二章-函数

2.1 prime

 #include<iostream>  
#include<stdio.h>  
#include<string>  
using namespace std;  

bool check(int n) //判断是否为质数   
{  
    if(n == 1)  
        return false;  
    if(n == 2)  
        return true;  
    else  
    {  
        for(int i=2;i < n;i++)  
        {  
            if(n % i == 0)  
                return false;  
            else   
                continue;  
        }  
        return true;  
    }  
}  

int arr[10086];  
int main()  
{  

    int n;  
    cin >> n;  

    int num;   
    int k;  
    int sum;   
    while(++n)  
    {  
        num = n;  
        k = 0;  
        sum = 0;  
        for(int j = 2;j <= num;j++)  
        {  
            if(num%j == 0&&check(j))  
            {  
                arr[k++] = j;  
                num/=j;  
                j --;  
            }  
            if(check(num))  
            {  
                arr[k] = num;  
                break;  
            }  
        }  
        for(int p = 0;p <= k;p++)  
        {  
        //  cout <<arr[p]<<" ";  
            sum += arr[p];  
        }  
        if(check(sum))  
            break;  
    }  

    cout << n;  

    return 0;  
}  

2.2 transformation

#include<iostream>  
#include<stdio.h>  
#include<string>  
using namespace std;  

char arr1[20][20];  
char arr2[20][20];  

int main()  
{  

    int n;  
    bool flag1,flag2,flag3;  
    char ccc;  
    while(cin >> n)  
    {  
        for(int i = 0;i < n; i++)  
        {  
            for(int j = 0; j < n; j++)  
                cin >> arr1[i][j];  
    //      cin >> ccc;  
        }  
        for(int k = 0; k < n; k++)  
        {  
            for(int t = 0; t < n ;t++)  
                cin >> arr2[k][t];  
    //      cin >> ccc;  
        }  


        flag1 = true;  
        flag2 = true;  
        flag3 = true;  
        for(int m = 0; m < n ;m++)   
            for(int p = 0; p <n ;p++)  
            {  
                if(arr2[p][n-m-1]!=arr1[m][p])  
                    {  
                        flag1 =false;  
                    //  if(flag1 ==false)  
                    //      cout << m << " " << p<<" "<<endl;  
                    }  
                if(arr2[m][n-p-1]!=arr1[m][p])  
                    flag2 = false;  
                if(arr2[p][m]!=arr1[m][p])  
                    flag3 = false;        
            }  

        if(flag1)  
            cout << "1" <<endl;  
        else if(flag2)  
            cout << "2" <<endl;  
        else if(flag3)  
            cout << "3" <<endl;  
        else  
            cout << "4" <<endl;  

    }  

    return 0;  
}  

2.3 Palindromes

#include<iostream>  
#include<stdio.h>  
#include<string>  
using namespace std;  

int arr[10086];  
int main()  
{  

    int s,n;  
    cin >> s >> n;  

    int len = 0;  
    int num;  
    bool check = true;  
    int result = 0;  
    while(s)  
    {  
        n++;  
        result = 0;  
        for(int j = 2;j<=10;j++)  
        {  
            num = n;  
            len = 0;  
            check = true;  
            while(num)  
            {  
                arr[++len] = num%j;  
                num/=j;  
            }  
            for(int k =1;k <= len;k++)  
                if(arr[k]!=arr[len-k+1])  
                {  
                    check = false;  
                    break;  
                }  
            if(check) result++;  
            if(result >= 2)  
            {  
                cout << n <<endl;  
                s--;  
                break;  
            }  
        }  
    }  

    return 0;  
}  

2.4 house

#include<iostream>  
#include<stdio.h>  
#include<string>  
using namespace std;  

int arr[200][200];  
int move[4][2] = { {-1,0} , {1,0} , {0,-1} , {0,1} };  

void DFS(int x,int y)  
{  
    arr[x][y] = 0;//搜索到的位置清零  

    int nextX,nextY;  

    for(int t=0;t<4;t++) //搜索上下左右   
    {  
        nextX = x + move[t][0];  
        nextY = y + move[t][1];  
        if(arr[nextX][nextY] == 1)  
            DFS(nextX,nextY);  
    }  
}  


int main()  
{  

    int n,m;  
    cin >> n >> m;  
    for(int i = 1; i <= n ;i++)  
    {  
        getchar();  
        for(int j = 1;j <= m;j++)  
            arr[i][j] = (getchar() == '1');  
    }  


    int num = 0;  
    for(int k = 1; k <= n; k++)  
        for(int p = 1; p <= m; p++)  
        {  
            if(arr[k][p] == 1)  
            {  
                num++;  
                DFS(k,p);     
            }  
        }  

    cout << num <<endl;  

    return 0;  
}  

2.5 Triangles

#include<iostream>  
#include<stdio.h>  
#include<string>  
using namespace std;  

int arr[15][15];//+为0 -为1   
int sum;//-号个数   
int num = 0;//满足题意的图形数   
int n;  
int i,j;  

void prin(int n)  
{  
    for(i = 1; i < n; i++)  
    {  
        for(j = 0; j < n-i;j++)  
        {  
            arr[i][j] = arr[i-1][j]+arr[i-1][j+1];  
            arr[i][j]%=2;  
        }   
    }  

    sum = 0;  
    for(i = 0; i < n; i++)  
        for(j = 0; j < n-i;j++)  
            if(arr[i][j]) sum++;   

    if(3*sum == n*(n+1))   
    {  
        num++;  
        for(i = 0; i < n; i++)  
        {  
            for(j = 0; j < n-i;j++)  
            {  
                if(arr[i][j]) cout << '-'<<" ";  
                else cout << '+'<<" ";  
            }  
            cout <<endl;  
        }  
    }  
}  

void search(int step)  
{  
    if(step >= n) prin(n);  
    else  
    {  
        arr[0][step] = 0; search(step+1);  
        arr[0][step] = 1; search(step+1);  
    }  
}  

int main()  
{  

    cin >> n;  

    search(0);  

    cout << num;   

    return 0;  
}