title: Find Pair With Greatest Product In Array
signature: function find_pair_with_greatest_product_in_array(arr, n)
test_code: 
  
  -- SOLUTION CODE
  -- ============================================
  PLACEHOLDER_CODE_BODY
  
  -- TESTING CODE 
  -- ============================================
  function isCorrect(actual, expected)
      if type(expected) ~= type(actual) then
          return false
      end
      
      if type(expected) == 'table' then
          for k,v_expected in pairs(expected) do
              
              if actual[k] == nil then
                  return false
              end
              local v_actual = actual[k]
              if not isCorrect(v_actual, v_expected) then
                  return false
              end
              actual[k]=nil
          end
      
          if next(actual) then 
              return false
          end
          return true
      else
          return actual == expected
      end
  end
  
  function validateSolution(actual, expected)
      return isCorrect(actual,expected)
  end
  
  function driver(arr, n, expected)
      local exec_result;
      local status, error_msg = pcall(function () 
          exec_result=PLACEHOLDER_FN_NAME(arr, n) 
      end)
      if status then
          if validateSolution(exec_result,expected) then
              return "PASSED"
          end
          return "FAILED"
      else
          return string.format("ERROR=%s",string.gsub(error_msg,".*:[%d]+: ",""))
      end
  end
      
  function main()
      result = driver({4, 78, 84}, 2, -1)
      print(string.format("TEST-0...%s",result))
  
      result = 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)
      print(string.format("TEST-1...%s",result))
  
      result = 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)
      print(string.format("TEST-2...%s",result))
  
      result = driver({39, 49, 94, 80, 48, 34, 63, 82, 47, 51, 60, 68, 79, 23, 97, 22, 54, 53, 40, 2, 25}, 10, -1)
      print(string.format("TEST-3...%s",result))
  
      result = driver({-90, -52, -10, 12, 72}, 3, -1)
      print(string.format("TEST-4...%s",result))
  
      result = driver({1, 0, 0}, 2, 0)
      print(string.format("TEST-5...%s",result))
  
      result = 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)
      print(string.format("TEST-6...%s",result))
  
      result = driver({4}, 0, -1)
      print(string.format("TEST-7...%s",result))
  
      result = 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)
      print(string.format("TEST-8...%s",result))
  
      result = 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)
      print(string.format("TEST-9...%s",result))
  
  end
  
  main()
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;
  }