HDU1042 N! 解题报告

N!

Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 43815    Accepted Submission(s): 12316

Problem Description

Given an integer N(0 ≤ N ≤ 10000), your task is to calculate N!

 

Input

One N in one line, process to the end of file.

 

Output

For each N, output N! in one line.

 

Sample Input

  
  

   
   1
2
3
  
  

 

Sample Output

  
  

   
   1
2
6
  
  

 

Author

JGShining（极光炫影）

#include<iostream>
using namespace std;
#define nn 8001
int main()
{
    int n;
    while(~scanf("%d",&n))
    {
        int i,j,a[nn];
        memset(a,0,sizeof(a));
        a[0]=1;
        for(i=2;i<=n;i++)
        {
            int c=0;
            for(j=0;j<nn;j++)
            {
                int s=a[j]*i+c;
                a[j]=s%100000;//每五个数放在一个字符里
                c=s/100000;
            }
        }
        for(i=nn-1;i>=0;i--)
            if(a[i])
                break;
            printf("%d",a[i]);//第一个数可能不满5个所以直接输出
            for(j=i-1;j>=0;j--)
                printf("%05d",a[j]);//1以后字符里的5个数里可能包含0要注意输出格式加%05d
            printf("\n");
    }
    return 0;
}