#include <stdio.h>
#include <string.h>

char x[150], sol[150];

int main()
{
    int i, j, T, ret;

    freopen("cifra.in", "r", stdin);
    freopen("cifra.out", "w", stdout);

    scanf("%d\n", &T);

    for (i = 1; i < 100; i ++)
    {
        ret = 1;
        for (j = 1; j <= i; j ++)
            ret = ret * i % 10;

        sol[i] = (sol[i - 1] + ret) % 10;
    }

    for (i = 1; i <= T; i ++)
    {
        gets(x + 1);
        int N = strlen(x + 1);

        if (N == 1)
            ret = x[1] - '0';
        else
            ret = (x[N - 1] - '0') * 10 + x[N] - '0';

        printf("%d\n", sol[ret]);
    }

    return 0;
}