#include <fstream>
using namespace std;
ifstream fin("cifra.in");
ofstream fout("cifra.out");
int v[20], w[20];
int main()
{
    short t;
    v[0]=0; v[1]=1; v[2]=4; v[3]=7; v[4]=6; v[5]=5; v[6]=6; v[7]=3; v[8]=6; v[9]=9; v[10]=0; v[11]=1; v[12]=6; v[13]=3; v[14]=6; v[15]=5; v[16]=6; v[17]=7; v[18]=4; v[19]=9;
    char c, c1='0', c2='0', c3='0';
    fin >> t;
    for(int i=1; i<=20; i++)
    {
        w[i]=(w[i-1]+v[i])%10;
    }
    fin.get(c);
    for(int i=1; i<=t; i++)
    {
        c1='0'; c2='0'; c3='0';
        while(fin.get(c)&&c!='\n')
        {
            c1=c2;
            c2=c3;
            c3=c;
        }
        fout << (((c2-'0'+(c1-'0')*10)/2)*4+w[(c2-'0')%2*10+c3-'0'])%10 << "\n";
    }
    return 0;
}