#include <cstdio>

int seven[10] = {0, 7, 4, 1, 8, 5, 2, 9, 6, 3};
int digit[2][10] = {
    {0, 1, 5, 2, 8, 3, 9, 2, 8, 7}, // 0, 1, 4, 7, 6, 5, 6, 3, 6, 9
    {0, 1, 7, 0, 6, 1, 7, 4, 8, 7}  // 0, 1, 6, 3, 6, 5, 6, 7, 4, 9
};

int main() {
    int ntests, a, b, c;
    FILE *fin, *fout;

    fin  = fopen("cifra.in",  "r");
    fout = fopen("cifra.out", "w");

    fscanf(fin, "%d\n", &ntests);
    while(ntests-- > 0) {
        for(a = b = '0'; (c = getc(fin)) != EOF && c != '\n'; a = b, b = c)
            ;
        fprintf(fout, "%d\n", (seven[a - '0'] + digit[a & 1][b - '0']) % 10);
    }

    return 0;
}