#include<stdio.h>
#include<math.h>
#include<iostream.h>
long long int u(long long int a)
{int u;
u=a%10;
return u;
}
int T,S,v[20],c1,c2,e;
long long N;
long a,b,i,j,k;

int main()
{
for(j=1;j<=19;j++)
{
c1=j%10;
if(j%4!=0) c2=j%4;
else c2=4;
e=pow(c1,c2);
S=S+u(e);
v[j]=u(S);
cout<<"v["<<j<<"]="<<v[j]<<endl;
}

FILE*in=fopen("cifra.in","r");
FILE*out=fopen("cifra.out","w");
fscanf(in,"%d",T);
k=N%20;
for(i=1;i<=T;i++)
{
S+=u((N/20)*13)+v[k];
S=u(S);
}
fcloseall();
return 0;
}