#include<cstdio>
using namespace std;
int main ()
{
    long long T,N,s,i,j,c,k,uc;
    freopen("cifra.in","r",stdin);
    scanf("%d",&T);
    freopen("cifra.out","w",stdout);
    for(i=1;i<=T;i++)
    {
        s=0;
        scanf("%d",&N);
        for(j=1;j<=N;j++)
        {
            uc=j%10;
            c=1;
            for(k=1;k<=j;k++)
                c*=uc;
            s+=c%10;
        }
		printf("%d\n",s);
    }
    return 0;
}