#include <fstream>
#include <iostream>

int main(int argc, const char * argv[]) {
    
    std :: ifstream input ("cifra.in");
    std :: ofstream output ("cifra.out");
    
    int n, t;
    int nr[102], sum;
    char *value = new char[102];

    input >> t;
    input.getline(value, 102);
        
    nr[0] = 0;
    for (int i = 1; i <= 99; ++i) {
        sum = 1;
        for (int j = 1; j <= i; ++j)
            sum = (sum * i) % 10;
        nr[i] = (sum + nr[i - 1]) % 10;
    };
        
    for (int i = 1; i <= t; ++i) {
        input.getline(value, 102);
        int numberOfDigits = strlen(value);
        n = numberOfDigits == 1 ? int(value[numberOfDigits - 1] - '0') :
            int(value[numberOfDigits - 2] - '0') * 10 + int(value[numberOfDigits - 1] - '0');
            
        output << nr[n] << "\n";
        std :: cout << nr[n] << "\n";
    };
    
    delete[] value;
    input.close();
    output.close();
    return 0;
}