#include <iostream>
#include <string>
#include <fstream>
#include <stdlib.h>

using namespace std;

const char *in_file_name = "cifra.in";
const char *out_file_name = "cifra.out";

int *double_digits = new int[100];

void die(bool assertion, const char *message)
{
    if (assertion) {
        fprintf(stderr, "(%s, %d): ",__FILE__, __LINE__);
        perror(message);
        exit(EXIT_FAILURE);
    }
}

int get_power(int n)
{
    int digit = 1;

    for (int i = 1; i <= n; i++)
        digit *= n, digit %= 10;

    return digit;
}

void set_double_vector()
{
    double_digits[0] = 0;
    for (int i = 1; i < 100; i++)
        double_digits[i] = (double_digits[i - 1] + get_power(i)) % 10;

}

int main()
{

    string line;
    string characters;
    char *results;
    int N, x, length = 0;

    ifstream in_file;
    ofstream out_file;

    in_file.open(in_file_name, ios::in);
    die(!in_file, "Error opening file for reading");

    out_file.open(out_file_name, ios::out);
    die(!out_file, "Error opening file for writing");

    getline(in_file, line);
    N = atoi(line.c_str());

    results = new char[N*2+10];

    set_double_vector();

    for (int i = 0; i < N; i++) {

        getline(in_file, line);

        length = line.length();

        if (length == 1) {
            x = line[length - 1] - '0';
        }
        else {
            x = ((line[length - 2] - '0') * 10) + (line[length - 1] - '0');
        }

        sprintf(results+2*i, "%d\n", double_digits[x]);

    }

    out_file << results;

    in_file.close();
    out_file.close();

    delete []results;
    delete []double_digits;

    return 0;
}