#include <fstream>
#include <cstring>
using namespace std;
char n[101];
int p[10]={0,1,4,7,6,5,6,3,6,9};

int main(){
    int t;
    ifstream fi("cifra.in");
    ofstream fo("cifra.out");
    fi>>t;
    for (int i=0;i<t;i++){
        fi>>n;
        int sum,l,k;
        l=strlen(n)-1;
        sum=0;
        if (l>1)k=(n[l-1]-48)*10+(n[l]-48);
        else k=n[l]-48;
        for (int j=1;j<=k;j++)
            sum+=p[j % 10];
        fo<<sum % 10<<endl;
        }
    return 0;
}