input: Write a function to find the GCD of two numbers. Use the Euclidean algorithm for the implementation. The function should take two parameters, a and b, and return their GCD. If the second number, b, is 0, the function should return the first number, a. Otherwise, the function should recursively call itself with the second number and the remainder of the first number divided by the second number.
  def findGCD(a, b): 
      if (b == 0): 
          return a
      return findGCD(b, a % b)
      
  assert findGCD(1000, 500) == 500
  assert findGCD(20, 8) == 4
  assert findGCD(15, 25) == 5
  assert findGCD(0, 10) == 10
  assert findGCD(10, 0) == 10
output: def findGCD(a, b): 
      if (b == 0): 
          return a
      return findGCD(b, a % b)