text: int nondet();
  
  void rec_t13(int x, int y){
      if(!(x>0)){
          return;
      }
  
      x=x-1;
      if (nondet()>0) 
        y=y+1;
      else
        while (y > 0)
          y=y-1;
      return rec_t13(x, y);
  }
  
  int main(int x, int y){
  	rec_t13(x, y);
  	return;
  }
  