#include <iostream>
#include <iomanip>
#include <fstream>
#include <cstdio>
#include <cmath>
#include <cstring>
#include <vector>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <algorithm>
#include <sstream>
#include <fstream>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
int P[][4] = {
{0,0,0,0},
{1,1,1,1},
{2,4,8,6},
{3,9,7,1},
{4,6,4,6},
{5,5,5,5},
{6,6,6,6},
{7,9,3,1},
{8,4,2,6},
{9,1,9,1}
};
int Modulo(string S) {
int X = 0;
for (int i = 0; i < S.length(); i++) {
X = (X * 10 + S[i] - '0') % 100;
}
return X;
}
int Solution(int X) {
int S = 0;
for (int i = 1; i <= X; i++) {
S = (S + P[i % 10][(i-1) % 4]) % 10;
}
return S;
}
int T, N;
string S;
int main(){
f >> T;
while (T--) {
f >> S;
g << Solution(Modulo(S)) << "\n";
}
return 0;
}