title: Triangular Numbers 1
signature: triangularNumbers1 :: Integer -> Bool
  triangularNumbers1 num = 
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 :: Bool -> Bool -> Bool
  validateSolution actual expected = do
      actual == expected
  
  
  driver :: Integer -> Bool -> String
  driver num expected = do
      if (validateSolution (PLACEHOLDER_FN_NAME num) expected)
          then "PASSED"
      else "FAILED"
  
  main = do
      printf "TEST-0...%s\n" (driver (1) (True) )
  
      printf "TEST-1...%s\n" (driver (3) (True) )
  
      printf "TEST-2...%s\n" (driver (6) (True) )
  
      printf "TEST-3...%s\n" (driver (10) (True) )
  
      printf "TEST-4...%s\n" (driver (55) (True) )
  
      printf "TEST-5...%s\n" (driver (48) (False) )
  
      printf "TEST-6...%s\n" (driver (63) (False) )
  
      printf "TEST-7...%s\n" (driver (72) (False) )
  
      printf "TEST-8...%s\n" (driver (16) (False) )
  
      printf "TEST-9...%s\n" (driver (85) (False) )
  
source_py: def triangular_numbers_1(num):
      if (num < 0):
          return False
      c = ((- 2) * num)
      (b, a) = (1, 1)
      d = ((b * b) - ((4 * a) * c))
      if (d < 0):
          return False
      root1 = (((- b) + math.sqrt(d)) / (2 * a))
      root2 = (((- b) - math.sqrt(d)) / (2 * a))
      if ((root1 > 0) and (math.floor(root1) == root1)):
          return True
      if ((root2 > 0) and (math.floor(root2) == root2)):
          return True
      return False
source_cpp: bool triangular_numbers_1(int num) {
    if ( num < 0 ) return false;
    int c = ( - 2 * num );
    int b = 1, a = 1;
    int d = ( b * b ) - ( 4 * a * c );
    if ( d < 0 ) return false;
    float root1 = ( - b + sqrt ( d ) ) / ( 2 * a );
    float root2 = ( - b - sqrt ( d ) ) / ( 2 * a );
    if ( root1 > 0 && floor ( root1 ) == root1 ) return true;
    if ( root2 > 0 && floor ( root2 ) == root2 ) return true;
    return false;
  }