#include <fstream>
#include <cstring>

using namespace std;

ifstream f ( "cifra.in" );
ofstream g ( "cifra.out" );

char S[10001];
int sum[] = { 0, 1, 5, 2, 8, 3, 9, 2, 8, 7, 7, 8, 4, 7, 3, 8, 4, 1, 5, 6, 6 };

int main()
{   int T, i;
    f >> T;
    for ( i = 1; i <= T; i++ ){
        f >> ( S + 1 );
        int n = strlen ( S + 1 );
        int a = 0, b = 0, c = 0, d = S[n] - '0';
        if ( n > 1 )
            a = S[n - 1] - '0';
        b = a - a % 2;
        if ( n > 2 )
            b += ( S[n - 2] - '0' ) % 2 * 10;
        b = b / 2;
        c = 8 * b % 10;
        d += ( a % 2 ) * 10;
        g << ( c + sum[d] ) % 10 << '\n';
    }
    return 0;
}