#include <iostream> #include <cstdio> using namespace std ; int a [21] ; int main ( ) { int n = 0 ; int t ; cin >> t ; t -= 16 ; if ( t == 0 ) { cout << 1 << endl ; return 0 ; } for ( int i = 0 ; i * 10 <= t ; i ++ ) { n += ( t - i ) * 10 / 5 } cout << n << endl ; return 0 ; }