ACM 阶乘的精确值

输入不超过1000的正整数n，输出n!=1*2*3*...*n的精确结果。
样例输入：30

样例输出：265252859812191058636308480000000

#include<stdio.h>  
int ans[40];  
int main()  
{  
    memset(ans, 0, sizeof(ans));  
    int n,c=0;  
    scanf("%d", &n);  
    ans[1] = 1;  
    for (int i = 2; i <= n; i++)  
    {  
        for (int j = 0; j < 40; j++)  
        {  
            int temp = ans[j] * i + c;  
            ans[j] = temp % 10;  
            c = temp / 10;  
        }  
    }  
    int p = 0;  
    for (int i = 39; i >= 0;i--)  
    if (ans[i] || p)  
    {  
        printf("%d", ans[i]); p = 1;  
    }  
    printf("\n");  
    //system("pause");  
    return 0;  
}