title: Find Pair With Greatest Product In Array
signature: findPairWithGreatestProductInArray :: [Integer] -> Integer -> Integer
  findPairWithGreatestProductInArray arr n = 
test_code: import Text.Printf
  import Control.Exception (catch, SomeException)
  import Data.Typeable
  import qualified Data.List as List
  import qualified Data.Map as Map
  import qualified Data.Set as Set
  
  -- SOLUTION CODE
  -- ============================================
  
  PLACEHOLDER_CODE_BODY
  
  -- TESTING CODE 
  -- ============================================
  validateSolution :: Integer -> Integer -> Bool
  validateSolution actual expected = do
      actual == expected
  
  
  driver :: [Integer] -> Integer -> Integer -> String
  driver arr n expected = do
      if (validateSolution (PLACEHOLDER_FN_NAME arr n) expected)
          then "PASSED"
      else "FAILED"
  
  main = do
      printf "TEST-0...%s\n" (driver ([4, 78, 84]) (2) (-1) )
  
      printf "TEST-1...%s\n" (driver ([-54, 64, 60, 14, 18, -68, -54, -58, 38, -72, -84, 46, 74, 76, 28, -2, 54, 24, 18, -74, -78, 14, -38, -70, 26, -54, -36, -96, -12, 8, 62, -42, -84, 10, -6, 36, -72, 10, 10, -20, 16, 92, -64, -34, 74, -98, 18]) (26) (76) )
  
      printf "TEST-2...%s\n" (driver ([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]) (22) (1) )
  
      printf "TEST-3...%s\n" (driver ([39, 49, 94, 80, 48, 34, 63, 82, 47, 51, 60, 68, 79, 23, 97, 22, 54, 53, 40, 2, 25]) (10) (-1) )
  
      printf "TEST-4...%s\n" (driver ([-90, -52, -10, 12, 72]) (3) (-1) )
  
      printf "TEST-5...%s\n" (driver ([1, 0, 0]) (2) (0) )
  
      printf "TEST-6...%s\n" (driver ([2, 9, 11, 14, 16, 17, 17, 18, 19, 21, 24, 25, 28, 29, 30, 33, 33, 39, 41, 41, 43, 46, 50, 51, 60, 62, 67, 80, 84, 86, 91, 92, 97]) (27) (60) )
  
      printf "TEST-7...%s\n" (driver ([4]) (0) (-1) )
  
      printf "TEST-8...%s\n" (driver ([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]) (16) (1) )
  
      printf "TEST-9...%s\n" (driver ([52, 8, 31, 92, 20, 18, 34, 5, 15, 8, 73, 20, 40, 61, 80, 51, 95, 73, 38, 30, 21, 69, 52, 38, 68, 77]) (22) (40) )
  
source_py: def find_pair_with_greatest_product_in_array(arr, n):
      result = (- 1)
      for i in range(n):
          for j in range((n - 1)):
              for k in range((j + 1), n):
                  if ((arr[j] * arr[k]) == arr[i]):
                      result = max(result, arr[i])
      return result
source_cpp: int find_pair_with_greatest_product_in_array(vector<int> arr, int n) {
    int result = - 1;
    for ( int i = 0;
    i < n;
    i ++ ) for ( int j = 0;
    j < n - 1;
    j ++ ) for ( int k = j + 1;
    k < n;
    k ++ ) if ( arr [ j ] * arr [ k ] == arr [ i ] ) result = max ( result, arr [ i ] );
    return result;
  }