#include <fstream>
#include <string>
using namespace std;

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

string s;
int v[10][3],T,i,c;

int main()
{
    fin>>T;

    v[1][1] = 1; v[1][2] = 1;
    v[2][1] = 5; v[2][2] =7;
    v[3][1] = 2; v[3][2] =0;
    v[4][1] = 8; v[4][2] = 6;
    v[5][1] = 3; v[5][2] = 1;
    v[6][1] = 9; v[6][2] = 7;
    v[7][1] = 2; v[7][2] = 4;
    v[8][1] = 8; v[8][2] =8;
    v[9][1] = 7; v[9][2] = 7;

    for (int i=1; i<=T; ++i)
    {
        fin>>s;
        int len = s.length();
        int c=0;

        if (len > 1)
        {
            c+=(s[len-2]-'0')*7;
        }

        if (len==1 || (s[len-2]-'0')%2==0)
        {
            c+=v[s[len-1]-'0'][1];
        }

        else
        {
            c+=v[s[len-1]-'0'][2];
        }
        fout<<c%10<<"\n";
    }
}