hdu 1042 N!

N!

Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 262144/262144 K (Java/Others)
Total Submission(s): 66786    Accepted Submission(s): 19147

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）

 

Recommend

We have carefully selected several similar problems for you:  1715 1047 1063 1753 1316 

 

基础的大数问题，注意进位，将数字全部压入数组保存。

 

题意：求n！，必须大数。

 

附上代码：

 

#include <cstdio>
#include <iostream>
using namespace std;
int main()
{
    int i,j,n,k,s,m,t;
    int a[100005];      //保存n!
    while(~scanf("%d",&n))
    {
        a[0]=1;
        s=1;    //记录数组的位数
        for(i=1; i<=n; i++)
        {
            k=0;       //记录进位的值
            for(j=0; j<s; j++)  //每一位都要乘以i
            {
                t=a[j]*i+k;
                a[j]=t%10;    //只保留个位数
                k=t/10;      //去掉最后一位
            }
            while(k)        //将k的值全部压入数组
            {
                a[s++]=k%10;
                k/=10;
            }
        }
        for(i=s-1; i>=0; i--) //注意倒着输出
            printf("%d",a[i]);
        printf("
");
    }
    return 0;
}