#include <fstream.h>
#include <stdlib.h>
#include <iostream.h>


fstream f("cifra.in",ios::in),g("cifra.out",ios::out);
int n,v[100],i;  char a[102];


int putere()
{int k=1,pt=1;
while(k<=i)  {pt=pt*i; pt%=10; k++;}
return pt;}

int generare()
{int var;
for(i=1;i<100;i++)
{if(i==0 || i==1 || i==5 || i==6)  {v[i]=(v[i-1]+i)%10;}
 else
{var=putere();
v[i]=(v[i-1]+var)%10;}}

}

int algoritm()
{n=atoi(a);  n%=100;
 g<<v[n]<<endl;}


main()
{generare(); f.getline(a,102);
while(f.getline(a,102))

  algoritm();

}