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

using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");

int u[100];

int ucif(int n){
    int uc=n%19,
        r=n%4,
        p=1;
    if (!r)
        r=4;
    while (r--)
        p*=uc;
    return p%10;
}
void precalcul(){
    for (int i=1;i<100;i++)
        u[i]=(u[i-1]+ucif(i))%10;
}
int main()
{
    int t,ncif,rest;
    char sir[101];
    precalcul();
    f>>t;
    while (t--){
        f>>sir;
        ncif=strlen(sir);
        rest=sir[ncif-1]-'0';
        if (ncif>=2)
            rest+=(sir[ncif-2]-'0')*10;
        g<<u[rest]<<'\n';
    }
    f.close();
    g.close();
    return 0;
}