title: Find The Number Occurring Odd Number Of Times
signature: find_the_number_occurring_odd_number_of_times <- function(arr, arr_size) {
test_code: 
  
  
  # SOLUTION CODE
  # ============================================
  PLACEHOLDER_CODE_BODY
  
  # TESTING CODE 
  # ============================================
  validate_solution <- function(actual, expected) {
      toString(actual)==toString(expected)
  }
  
  driver <- function(arr, arr_size, expected){
      if (validate_solution(PLACEHOLDER_FN_NAME(arr, arr_size), expected)){
          "PASSED"
      } else{
          "FAILED"
      }
  }
  
  main <- function() {
      cat(sprintf("TEST-0...%s\n",driver(
          list(1L, 5L, 5L, 8L, 14L, 15L, 17L, 17L, 18L, 23L, 23L, 25L, 26L, 35L, 36L, 39L, 51L, 53L, 56L, 56L, 60L, 62L, 64L, 64L, 65L, 66L, 67L, 68L, 71L, 75L, 80L, 82L, 83L, 88L, 89L, 91L, 91L, 92L, 93L, 95L, 99L), 31L, 
          1L
      )))
  
      cat(sprintf("TEST-1...%s\n",driver(
          list(-56L, 98L, 44L, 30L, -88L, 18L, 60L, 86L, 4L, 16L, 10L, 64L, -22L, -86L, -66L, -16L, 70L, -44L, 98L, 78L, -96L, -66L, 92L, 10L, 40L, -16L), 19L, 
          -56L
      )))
  
      cat(sprintf("TEST-2...%s\n",driver(
          list(0L, 0L, 0L, 0L, 0L, 1L, 1L, 1L), 6L, 
          0L
      )))
  
      cat(sprintf("TEST-3...%s\n",driver(
          list(36L, 11L, 83L, 41L, 42L, 14L, 46L, 89L, 91L, 96L, 57L, 42L, 74L, 73L, 9L, 26L, 79L, 40L, 31L, 69L, 44L, 39L, 14L, 92L, 34L, 20L, 52L, 47L, 14L), 25L, 
          36L
      )))
  
      cat(sprintf("TEST-4...%s\n",driver(
          list(-84L, -84L, -84L, -78L, -66L, -62L, -62L, -36L, -24L, -10L, -10L, -8L, -4L, -2L, 12L, 14L, 20L, 22L, 36L, 42L, 46L, 66L, 84L, 96L, 96L, 98L), 23L, 
          -84L
      )))
  
      cat(sprintf("TEST-5...%s\n",driver(
          list(1L, 1L, 0L, 1L, 0L, 1L, 1L, 0L, 1L, 1L, 0L, 1L, 0L, 1L, 0L, 1L, 0L, 0L, 1L, 1L, 1L, 0L, 1L, 1L, 1L, 1L, 1L, 1L), 19L, 
          1L
      )))
  
      cat(sprintf("TEST-6...%s\n",driver(
          list(11L, 12L, 14L, 28L, 42L, 48L, 50L, 58L, 67L, 74L, 86L, 89L, 95L), 7L, 
          11L
      )))
  
      cat(sprintf("TEST-7...%s\n",driver(
          list(52L, -56L, -6L, 74L, 10L, 68L, 74L, 10L, 16L, -80L, 82L, -32L, 6L, -6L, 82L, 20L), 11L, 
          52L
      )))
  
      cat(sprintf("TEST-8...%s\n",driver(
          list(0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), 31L, 
          0L
      )))
  
      cat(sprintf("TEST-9...%s\n",driver(
          list(4L, 80L, 92L), 1L, 
          4L
      )))
  
  }
  
  main()
source_py: def find_the_number_occurring_odd_number_of_times(arr, arr_size):
      for i in range(0, arr_size):
          count = 0
          for j in range(0, arr_size):
              if (arr[i] == arr[j]):
                  count += 1
          if ((count % 2) != 0):
              return arr[i]
      return (- 1)
source_cpp: int find_the_number_occurring_odd_number_of_times(vector<int> arr, int arr_size) {
    for ( int i = 0;
    i < arr_size;
    i ++ ) {
      int count = 0;
      for ( int j = 0;
      j < arr_size;
      j ++ ) {
        if ( arr [ i ] == arr [ j ] ) count ++;
      }
      if ( count % 2 != 0 ) return arr [ i ];
    }
    return - 1;
  }