C :

#include <stdio.h>
#include <math.h>

int main()
{
	int n;
	int data;
	long double weishu;
	scanf("%d", &n);
	while (n--)
	{
		scanf("%d", &data);
		weishu = 0;
		for (int i = 1; i <= data; i++)
		{
			weishu = weishu + log10(i*1.0);
		}
		printf("%d\n", (int)floor(weishu) + 1);
	}
	return 0;
}

C++ :

#include<stdio.h>
#include<cmath>
using namespace std;
int main()
{
    int n,m,i;
    double ans;
    scanf("%d",&n);
    while(n--)
    {
              scanf("%d",&m);
              ans=1;
              for(i=2; i<=m; i++)
              ans+=log10(i);
              printf("%d\n",(int)ans);
    }
    return 0;
}