100%AC不AC我倒立洗头

#include<iostream>
#include<cstring>
#include<cmath>
#include<iomanip>
#include<queue>
#include<algorithm>
#include<vector>
#include<stack>
using namespace std;
#define LL long long
const int N=1e5+10;
using namespace std;
int n , ans[N] , len , x;
int main()
{
	
	cin>>n;
	ans[++len] = 1;
	for(int i = 2; i <= n; i++)
	{
		for(int j = 1; j <= len; j++)
		{
			ans[j] = ans[j] * i + x;
			x = ans[j] / 10;
			ans[j] %= 10;
		}
		
		while( x )
		{
			ans[++len] = x % 10;
			x /= 10;
		}
	}
	for(int i = len; i >= 1; i --)
		cout << ans[i];
	return 0;
}