#include <iostream>

using namespace std;

float fency_price(float l, float c)
{
    float perimeter = 4.0*l;
    float result = perimeter*c;
    return result;
}

int main()
{
   float side_length, fence_cost, total_price;

   cout << "input fency's side length and fence cost";
   cin >> side_length >> fence_cost;

   total_price = fency_price(side_length, fence_cost);

   cout << "sad old man will pay for that " << total_price;
   return 0;
}