#include <stdio.h>

#define PI 3.1415927
//---------------------------------------------------------------------------
int main(int argc, char **argv)
{
  int volba;
  float a,b;
  do
  {
    printf("1 ... Zadani stran\n");
    printf("2 ... Obsah\n");
    printf("3 ... Obvod\n");
    printf("4 ... Konec\n");
    printf("---------------------\n");
    printf("Volba: ");
    volba= 0;
    scanf("%d",&volba);
    
    
    
  } while (volba!= 4);
  return 0;
}