#include <fstream>
#include <iostream>
using namespace std;
int main()
{
    ifstream fin("cifra.in");
    ofstream fout("cifra.out");
    int n, nr,i,sum, x, uc;
    fin>>n;
    while(n>0) {
        fin>>nr;
        sum=0;
        for(i=1;i<=nr;i=i+1){
            uc = i % 10;
            if(uc == 0) {
                x = 0;
            }
            else if(uc == 1) {
                x = 1;
            }
            else if(uc == 2) {
                if(i%4==1)
                    x = 2;
                if(i%4==2)
                    x = 4;
                if(i%4==3)
                    x = 8;
                if(i%4==0)
                    x = 6;
            }
            else if(uc == 3) {
                if(i%4==1)
                    x = 3;
                if(i%4==2)
                    x = 9;
                if(i%4==3)
                    x = 7;
                if(i%4==0)
                    x = 1;
            }
            else if(uc == 4) {
                if(i%2==1)
                    x = 4;
                if(i%2==0)
                    x = 6;
            }
            else if(uc == 5) {
                x = 5;
            }
            else if(uc == 6) {
                x = 6;
            }
            else if(uc == 7) {
                if(i%4==1)
                    x = 7;
                if(i%4==2)
                    x = 9;
                if(i%4==3)
                    x = 3;
                if(i%4==0)
                    x = 1;
            }
            else if(uc == 8) {
                if(i%4==1)
                    x = 8;
                if(i%4==2)
                    x = 9;
                if(i%4==3)
                    x = 3;
                if(i%4==0)
                    x = 1;
            }
            else if(uc == 9) {
                if(i%2==1)
                    x = 9;
                if(i%2==0)
                    x = 1;
            }
            sum = sum + x;
            sum = sum % 10;
        }
        fout<<sum<<'\n'; // endl
        n=n-1;
    }
    fin.close();
    fout.close();
    return 0;
}