input: Write a function to convert a number into its binary format. If the number is 0, return 0.
  def convert_to_binary(num):
      if num == 0:
          return 0
      
      binary = ''
      while num != 0:
          remainder = num % 2
          binary = str(remainder) + binary
          num = num // 2
      
      return binary
  
  print(convert_to_binary(10))  # 1010
output: def convert_to_binary(num):
      if num == 0:
          return 0
      
      binary = ''
      while num != 0:
          remainder = num % 2
          binary = str(remainder) + binary
          num = num // 2
      
      return binary