#include <iostream>
using namespace std;
int main()
{
float x = 15;
int l;

  cout<<"Lvl: ";
  cin >> l;
  cin.ignore();
  for ( int i = 1; i < l-1; i++) {
    x = x * 1.2;
    x -= (int)x % 1;
  }
  cout<< x <<endl;
  cin.get();
}