#include <iostream>
#include <fstream>

using namespace std;

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

int ultcifPutere(int x, int e){
    if(e==0) return 1;
    if(e%2==0) return ultcifPutere(x * x % 10, e/2);
    return x * ultcifPutere(x * x %10, e/2) % 10;
}

int main()
{
    int t, sm, nr;
    char c, x;
    fin>>t; fin.get();

    sm=0; nr=0;
    while(fin.get(c)){
        if(c=='\n'){
            nr++;
            sm = (sm + ultcifPutere(x - '0', nr) ) % 10;

            fout<<sm<<"\n";
        }

        else x=c;
    }

}