title: How To Check If A Given Array Represents A Binary Heap
signature: function howToCheckIfAGivenArrayRepresentsABinaryHeap($arr, $i, $n) {
test_code: <?php
  
  
  // SOLUTION CODE 
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE 
  // ============================================
  function validateSolution($actual, $expected){
      return serialize($actual) == serialize($expected);
  }
  
  function driver($arr, $i, $n, $expected){
      try{
        if (validateSolution(PLACEHOLDER_FN_NAME($arr, $i, $n), $expected)){
          return "PASSED";
        }
        return "FAILED";
      }
      catch (Exception $exception_obj) {
        return get_class($exception_obj);
      }
  }
  
  function main(){
      printf("TEST-0...%s\n",driver(
        array(1, 2, 3, 5, 24, 24, 25, 25, 36, 37, 37, 39, 42, 44, 46, 50, 51, 54, 56, 60, 62, 70, 71, 73, 75, 80, 80, 85, 86, 89, 91, 95, 99), 0, 18, 
        false));
      
      printf("TEST-1...%s\n",driver(
        array(-44, -58, 88, -42, 42, -14, -44, 42, 64, 94, -46, -70, 34, -10, -46, -52, -6, -78, 64, 56, 74, 98, -34, -4, -92, 6, -52, -20, 78, -72, -40), 0, 27, 
        false));
      
      printf("TEST-2...%s\n",driver(
        array(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1), 0, 20, 
        false));
      
      printf("TEST-3...%s\n",driver(
        array(10, 2, 1, 34, 21, 37, 49, 31, 70, 97, 87, 50, 76, 55), 0, 8, 
        false));
      
      printf("TEST-4...%s\n",driver(
        array(-94, -84, -82, -66, -64, -62, -56, -38, -24, -24, -4, 2, 4, 4, 8, 14, 16, 20, 30, 34, 34, 48, 58, 58, 70, 76, 78, 86, 88, 96, 98), 0, 26, 
        false));
      
      printf("TEST-5...%s\n",driver(
        array(1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0), 12, 11, 
        true));
      
      printf("TEST-6...%s\n",driver(
        array(5, 20, 30, 5, 10, 21, 5), 0, 7, 
        false));
      
      printf("TEST-7...%s\n",driver(
        array(50, 20, 30, 5, 10, 21, 5), 0, 7, 
        true));
      
      printf("TEST-8...%s\n",driver(
        array(50, 20, 30, 5, 10, 21, 5), 2, 7, 
        true));
      
      printf("TEST-9...%s\n",driver(
        array(50, 20, 30, 5, 10, 21, 5), 4, 7, 
        true));
      
  }
  
  main();
  ?>
source_py: def how_to_check_if_a_given_array_represents_a_binary_heap(arr, i, n):
      if (i > int(((n - 2) / 2))):
          return True
      if ((arr[i] >= arr[((2 * i) + 1)]) and (arr[i] >= arr[((2 * i) + 2)]) and how_to_check_if_a_given_array_represents_a_binary_heap(arr, ((2 * i) + 1), n) and how_to_check_if_a_given_array_represents_a_binary_heap(arr, ((2 * i) + 2), n)):
          return True
      return False
source_cpp: bool how_to_check_if_a_given_array_represents_a_binary_heap(vector<int> arr, int i, int n) {
    if ( i > ( n - 2 ) / 2 ) return true;
    if ( arr [ i ] >= arr [ 2 * i + 1 ] && arr [ i ] >= arr [ 2 * i + 2 ] && how_to_check_if_a_given_array_represents_a_binary_heap ( arr, 2 * i + 1, n ) && how_to_check_if_a_given_array_represents_a_binary_heap ( arr, 2 * i + 2, n ) ) return true;
    return false;
  }