#include <stdio.h>
#include <string.h>
#define DIMMAX 101
  
char N[DIMMAX];
int T, dim;
int cp[]={0, 1, 4, 7, 6, 5, 6, 3, 6, 9};
  
int main (){
	int i, j, s, nat;
	FILE *pf, *pg;   
	pf = fopen ("cifra.in", "r");
    pg = fopen ("cifra.out", "w");

    fscanf(pf, "%d", &T);
    for(i = 1; i <= T; i++){   
        fscanf(pf, "%s", N);
        dim = strlen(N);
		nat = N[dim - 1] - '0';

        s = 0;
		for(j = 1; j <= nat; j++)
			s += cp[j % 10];
        fprintf(pg, "%d\n", s % 10);
    }
    fclose(pf);
	fclose(pg);
    return 0;
}