#include <fstream>
#include <cstring>
#include <algorithm>

using namespace std;

ifstream fin("cifra.in");
ofstream fout("cifra.out");

int m[2][10] = {{0, 1, 4, 7, 6, 5, 6, 3, 6, 9},
                {0, 1, 6, 3, 6, 5, 6, 7, 4, 9}};

int main()
{
    int t, x, n, a, b;
    bool r;
    char v[101];

    fin >> t;

    while(t--) {
        memset(v, 0, 101);

        fin >> v;

        x = 0;
        while(v[x])
            x++;

        n = 0, r = false, x--, a = (int)v[x] - 48;
        if(x)
        {
            b = (int)v[x - 1] - 48;
            n += (7 * b) % 10;

            r = (b & 1) ? 1 : 0;
        }

        for(int i = 1; i <= a; i++) {
            n += m[r][i];
        }

        fout << n % 10 << '\n';
    }

    return 0;
}