#include <fstream>
#include <string.h>
using namespace std;

int t, v[101];
char n[102];

int uCif(int x) {
    int b = x%10;
    int e = x%4;
    if(!e)
        e = 4;
    int p = 1;
    for(int i = 1; i <= e; i++)
        p *= b;
    return p;
}

int main() {
    ifstream f("cifra.in");
    ofstream g("cifra.out");
    f >> t;
    for(int i = 1; i <= 100; i++)
        v[i] = (v[i-1] + uCif(i))% 10;

    for(int q = 0; q < t; q++) {
        f >> n;
        int x = strlen(n);
        if(x == 1)
            g << v[n[0]- '0'] << endl;
        else
            g << v[n[x-1]-'0' + 10*n[x-2]-'0'] << endl;
    }

    f.close();
    g.close();
    return 0;
}