#include <iostream>
#include <clocale>
#define a 1000
#define b 5000
#define c 10000
using namespace std;
int main()
{
  int  d;
  double pod;
  setlocale(LC_CTYPE,"rus");
  cout<<"Ââåäiòü d\n";
  cin>>d;
  if (d < a) pod = 0;
  else if (d < b) pod = 0.125*(d - a);
  else if (d < c) pod = 0.125*(b - a) + 0.25*(d - b);
  else pod = 0.125*(b - a) + 0.25*(c - b) + 0.5*(d - c);
  cout<<"Ïîäàòîê äîðiâíþº "<<pod;
  return 0;
}