// Example program
#include <iostream>
#include <string.h>
#include <fstream>
using namespace std;
ifstream f("cifra.in");
ofstream o("cifra.out");
int n,p;
int main()
{f>>n;
while(f>>n)
    {p=0;
        for(int i=1;i<=n;i++)
        {
        if(i%5==0 || i%5==1 || i%5==4)
            {if(i%10==4){p+=6;continue;}
                p+=i%10;continue;}
        if(i%2==0)
        {
            if((i/2)%2==0)
            {
                p+=6;continue;
            }
            else
            {
                p+=4;continue;
            }
        }
        if(i%2==1)
        {
              //  if((i+1)%5==4)
              //  {p+=7;continue;}
              //  else
            //   {p+=3;continue;}
            if((i/3)%2==0)
                {p+=3;continue;}
            else
                {p+=7;continue;}

        }
        }
o<<p%10;
    }
  // cout<<p<<"["<<n<<"]\n";

return 0;}