#include <cstdio>
#include <string.h>
using namespace std;

FILE *f = freopen("cifra.in", "r", stdin), *g = freopen("cifra.out", "w", stdout);

int main()
{
	int t, U, u, n;
	char N[105];
	scanf("%d", &t);
	while(t)
        {
            scanf("%s", &N);

            if(strlen(N) == 1)
            {
                n = N[0] - 48;
                U = 0;
            }else if(strlen(N) == 2){

                n = N[1] - 48 + (N[0] - 48) % 2 * 10;
                U = (N[0] - 48) / 2 * 4;
            }else{

                n = N[strlen(N) - 1] - 48 + N[strlen(N) - 2] % 2 * 10;
                U = (N[strlen(N) - 2] - 48 + (N[strlen(N) - 3] - 48) % 2 * 10) / 2 * 4 % 10;
            }

            for(int i = 1; i <= n; ++i)
                {
                    u = 1;
                    for(int j = 1; j <= i; ++j)
                        {
                            u = u * i % 10;
                        }
                    U = (U + u) % 10;
                }
            printf("%d\n", U);
            --t;
        }
}