#include <iostream>
#include <fstream>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
int sol[100];
string s;
int UltCif(int n)
{
    int uc = n % 10, r = n % 4, p = 1;
    if(r == 0)
        r = 4;
    while(r--)
        p = p * uc;
    return p % 10;
}
void precalc()
{
    for(int i = 1; i < 100; i++)
        sol[i] = (sol[i - 1] + UltCif(i)) % 10;
}
void rezolvare()
{
    f >> s;
    int n = s.size(), x;
    if(n == 1)
        x = s[0] - '0';
    else
        x = (s[n - 2] - '0') * 10 + (s[n - 1] - '0');
    g << sol[x] << '\n';
}
int main()
{
    precalc();
    int T;
    f >> T;
    while(T--)
        rezolvare();
    f.close();
    g.close();
    return 0;
}