#include <iostream>
#include<cstdio>
#include<string.h>
#include<string>
#include<fstream>
using namespace std;
int pref[100];
int putere(int x){
  int i;
  int r=1;
  for(i=1;i<=x;i++)
    r=(r*(x%10))%10;
  return r;
}
string s;
ifstream fin("cifra.in");
ofstream fout("cifra.out");
int main()
{

    int i;
    for(i=1;i<100;i++){
      pref[i]=(pref[i-1]+putere(i))%10;
    }
    int n,c,num;
    fin>>n;
    for(i=1;i<=n;i++){
       fin>> s;
      c=s.length();
      if(c<2)
        num=s[c-1]-'0';
      else
        num=(s[c-2]-'0')*10+s[c-1]-'0';
      fout<<pref[num]<<"\n";
    }
    return 0;
}