#include <iostream>
#include <fstream>
#include <cstring>

using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
int v[100];
char N[101];
int ultcif(int x)
{
    int uc=1, rest=x%4;
    if(rest==0)
    rest=4;
    for(int i=1;i<=rest;i++)
    {
        uc=uc*(x%10);
    }
    return uc%10;
}


int main()
{
    int T,i,x;
    f>>T;
    v[0]=0;
    for(i=1;i<=99;i++)
    {
        v[i]=(ultcif(i)+v[i-1])%10;
    }
    while(T--)
    {
        f>>N;
        int lungime=strlen(N);
        if(lungime==1)
        x=N[0]-'0';
        else
        x=(N[lungime-2]-'0')*10+(N[lungime-1]-'0');
        g<<v[x]<<'\n';;

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