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

int main()
{
    ifstream f("cifra.in");
    ofstream g("cifra.out");
    int t,i,suma;
    char pc,rest,x[10000];
    f>>t;
    f.getline(x,10000,'\n');
    for(i=1;i<=t;i++)
    {
        f.getline(x,10000,'\n');
        /*rest='0';
        pc='0';
        g<<x<<" ";
        while(x>='0'&&x<='9')
        {
            pc=rest;
            rest=x;
            f>>x;
        }*/
        if(strlen(x)==1)
        {pc='0';
        rest=x[0];}
        else
        {
            pc=x[strlen(x)-2];
            rest=x[strlen(x)-1];
        }
        if(rest=='2')
        rest='5';
        else
        if(rest=='3')
        rest='2';
        else
        if(rest=='4')
        rest='8';
        else
        if(rest=='5')
        rest='3';
        else
        if(rest=='6')
        rest='9';
        else
        if(rest=='7')
        rest='2';
        else
        if(rest=='9')
        rest='7';
        suma=(pc-'0')*7+(rest-'0');
        suma=suma%10;
        g<<suma<<endl;

    }
    return 0;
}