title: Triangular Numbers 1
signature: triangular_numbers_1 <- function(num) {
test_code: 
  
  
  # SOLUTION CODE
  # ============================================
  PLACEHOLDER_CODE_BODY
  
  # TESTING CODE 
  # ============================================
  validate_solution <- function(actual, expected) {
      toString(actual)==toString(expected)
  }
  
  driver <- function(num, expected){
      if (validate_solution(PLACEHOLDER_FN_NAME(num), expected)){
          "PASSED"
      } else{
          "FAILED"
      }
  }
  
  main <- function() {
      cat(sprintf("TEST-0...%s\n",driver(
          1L, 
          TRUE
      )))
  
      cat(sprintf("TEST-1...%s\n",driver(
          3L, 
          TRUE
      )))
  
      cat(sprintf("TEST-2...%s\n",driver(
          6L, 
          TRUE
      )))
  
      cat(sprintf("TEST-3...%s\n",driver(
          10L, 
          TRUE
      )))
  
      cat(sprintf("TEST-4...%s\n",driver(
          55L, 
          TRUE
      )))
  
      cat(sprintf("TEST-5...%s\n",driver(
          48L, 
          FALSE
      )))
  
      cat(sprintf("TEST-6...%s\n",driver(
          63L, 
          FALSE
      )))
  
      cat(sprintf("TEST-7...%s\n",driver(
          72L, 
          FALSE
      )))
  
      cat(sprintf("TEST-8...%s\n",driver(
          16L, 
          FALSE
      )))
  
      cat(sprintf("TEST-9...%s\n",driver(
          85L, 
          FALSE
      )))
  
  }
  
  main()
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;
  }