#include <stdlib.h>
#include <stdio.h>


int fact0 ( int p)
{
  int x = 0;
for ( int i = 0 ; i < p ; i++, x+=5);

printf("%i",x);

}

int main()
{
 freopen("fact.in","r",stdin);
 freopen("fact.out","w",stdout);

 int p;
 scanf("%i",&p);
 fact0(p);

}