#include <cstdio>
#include <cstring>
using namespace std;
const int MAX_CF = 100;
int sp[] = {0, 1 ,5 ,2 ,8 ,3 ,9 ,2 ,8, 7};
char s[MAX_CF + 5];
int main(){
    freopen("cifra.in", "r", stdin);
    freopen("cifra.out", "w", stdout);
    int t, n, i, last;
    scanf("%d ", &t);
    for (i = 1; i <= t; i ++){
        gets(s);
        n = strlen(s);
        last = sp[(s[n - 1] - '0')];
        if (n > 1)
            last += (s[n - 2] - '0') * 7;
        printf("%d\n", last % 10);
    }
    return 0;
}