#include <iostream>
#include <fstream>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
int i,v[30000],j,s=0,T;
void citire(int v[30000],int &T)
{
    f>>T;
    for(i=0;i<T;i++)
    {
        f>>v[i];
    }
}
int powe (int a)
{
    long long b=a;
    int sol=1;
    while(b)
    {
        if(b%2==1){
            sol=sol*a%10;
        }
        a=a*a%10;
        b/=2;
    }
    cout<<sol<<"\n";
    return sol;
}
void cifra(int v[30000],int T)
{
    for(i=0;i<T;i++)
    {
        s=0;
        for(j=1;j<=v[i];j++)
        {
            s=s+powe(j)%10;
        }
        g<<s%10<<"\n";
        cout<<"\n";
    }
}
int main()
{
    citire(v,T);
    cifra(v,T);
    return 0;
}