title: Elements To Be Added So That All Elements Of A Range Are Present In Array
signature: function elementsToBeAddedSoThatAllElementsOfARangeArePresentInArray(arr, n) {
test_code: 
  
  // SOLUTION CODE
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE 
  // ============================================
  function convertToString(value) {
      return JSON.stringify(value, function (key, val) {
          if (val instanceof Set) {
              return Array.from(val);
          } return val;});
  }
  
  function validateSolution(actual, expected){
      return convertToString(actual)===convertToString(expected);
  }
  
  function driver(arr, n, expected){
      try{
          if (validateSolution(PLACEHOLDER_FN_NAME(arr, n),expected)){
              return "PASSED";
          }
          return "FAILED";
      } catch (error) {
        return error.name;
      }
      
  }
      
  function main(){
    let result = '';
    result = driver([4, 4, 5, 7, 7, 9, 13, 15, 18, 19, 25, 27, 27, 29, 32, 36, 48, 51, 53, 53, 55, 65, 66, 67, 72, 74, 74, 76, 77, 79, 80, 81, 82, 83, 83, 86, 87, 97, 98, 98, 99], 30, 51);
    console.log(`TEST-0...${result}`);
  
    result = driver([-90, -90, -88, -84, -84, -84, -80, -74, -52, -26, -26, -16, -8, 6, 14, 16, 34, 64, 72, 92, 94], 17, 112);
    console.log(`TEST-1...${result}`);
  
    result = driver([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, 1], 24, 0);
    console.log(`TEST-2...${result}`);
  
    result = driver([10, 12, 12, 13, 13, 23, 25, 26, 29, 32, 39, 43, 43, 54, 62, 79, 92], 14, 34);
    console.log(`TEST-3...${result}`);
  
    result = driver([-94, -86, -72, -64, -64, -58, -56, -56, -56, -56, -54, -54, -52, -42, -42, -40, -36, -32, -28, -22, -20, -18, -12, -8, -6, -4, 0, 2, 4, 10, 16, 30, 32, 48, 48, 60, 70, 74, 76, 84], 35, 115);
    console.log(`TEST-4...${result}`);
  
    result = driver([0, 0, 0, 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], 29, 0);
    console.log(`TEST-5...${result}`);
  
    result = driver([4, 5, 8, 12, 16, 16, 17, 20, 20, 23, 26, 26, 27, 28, 32, 34, 40, 40, 41, 41, 44, 45, 47, 49, 51, 52, 54, 57, 60, 62, 63, 64, 66, 68, 69, 70, 71, 76, 77, 80, 80, 80, 90, 91, 92, 94, 96, 98, 99], 42, 42);
    console.log(`TEST-6...${result}`);
  
    result = driver([-98, -92, -92, -92, -92, -86, -78, -74, -72, -68, -60, -52, -48, -48, -46, -46, -44, -40, -38, -26, -18, 2, 4, 4, 10, 14, 14, 16, 20, 38, 48, 48, 50, 56, 60, 66, 74, 76, 80, 84, 88, 96, 96, 96], 37, 144);
    console.log(`TEST-7...${result}`);
  
    result = driver([0, 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, 1, 1], 17, 0);
    console.log(`TEST-8...${result}`);
  
    result = driver([49, 66, 84], 2, 16);
    console.log(`TEST-9...${result}`);
  
    process.exit(0);
  };
  
  if (require.main === module) {
    main();
  }
source_py: def elements_to_be_added_so_that_all_elements_of_a_range_are_present_in_array(arr, n):
      count = 0
      arr.sort()
      for i in range(0, (n - 1)):
          if ((arr[i] != arr[(i + 1)]) and (arr[i] != (arr[(i + 1)] - 1))):
              count += ((arr[(i + 1)] - arr[i]) - 1)
      return count
source_cpp: int elements_to_be_added_so_that_all_elements_of_a_range_are_present_in_array(vector<int> arr, int n) {
    int count = 0;
    sort(arr.begin(), arr.end());
    for ( int i = 0;
    i < n - 1;
    i ++ ) if ( arr [ i ] != arr [ i + 1 ] && arr [ i ] != arr [ i + 1 ] - 1 ) count += arr [ i + 1 ] - arr [ i ] - 1;
    return count;
  }