//#include <iostream>
#include <fstream>
using namespace std;
ifstream cin("cifra.in");
ofstream cout("cifra.out");
string s;
int rest20(){
    int n=s.size(),a=0;
    for(int i=max(0,n-2);i<=n-1;i++){
        a=a*10+s[i]-'0';
    }
    return a%20;
}
int calc20(){
    int n=s.size(),sum=0;
    for(int i=max(0,n-6);i<n;i++){
        sum*=10;
        sum+=s[i]-'0';
    }
    return ((sum/20)%5);
}
int rest[]={1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,0};
int que(int a){
    int sum=0;
    for(int i=0;i<a;i++){
        sum+=rest[i];
    }
    return sum;
}
int main()
{
    int n,sum=0;
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>s;
        //cout<<rest20()<<" "<<rest100()<<"\n";
        //cout<<calc20()<<"\n";
        int rasp=(calc20()*4+que(rest20()))%10;
        cout<<rasp<<"\n";
    }
    return 0;
}