#include <fstream>
#include <cstring>
#define max 100010
using namespace std;

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

int N, M, i,v[max], x;
char s[max];int T, nr;

int suma(int x)
{
 int s=0,p,k,j;
 for(k=1;k<=x;k++)
 {
     p=1;
     for(j=1;j<=k;j++) {p*=k; if (p>=10) p%=10;}
     s+=p;
 }
 return s%10;
}

void Cifra(){
     f >> T;
     for(i = 1; i <= T; i ++){
          f >> (s + 1);
          s[0] = '0';
          N = strlen(s + 1);
          nr = (s[N-1]-'0')*10+(s[N]-'0');
          g << v[nr] << "\n";
     }
     return;
}

int main(){
    for(i=1;i<=100;i++) v[i]=suma(i);
     Cifra();
}