大数相乘

#include <iostream>
#include <cstdio>
using namespace std;
int f[100];
int cnt=1;
int main()
{
    int n ;
    for(int i = 0; i < 100; i ++)
        f[i] = 0;
    f[0] = 1;
    cin >> n ;
    int c = 0;
    for(int i = 1; i <= n; i ++){
        for(int j = 0; j < cnt; j ++){
            f[j]= f[j]*i+c;
            c = f[j]/10;
            f[j]%=10;
        }
        if(c){
            f[cnt++] = c;
        }
        c = 0;
    }
    for(int i = cnt-1; i >=0; i --)
        cout << f[i];
    cout << endl;
    return 0;
}