UVa 568 - Just the Facts

WA 了好几次，只保留一位数不够。

代码如下：

#include<iostream>
#include<cstdio>

using namespace std;

long long a[10001];

int main()
{
    long long n, i, t;
    a[0]=1;
    for (i=1; i<=10000; i++)
    {
        t=a[i-1]*i;
        while(t%10 == 0)
            t/=10;
        a[i]=t%100000;    //就是这，a[i]=t%10;
    }
    while(cin >> n)
        printf("%5lld -> %lld\n", n, a[n]%10);
    return 0;
}