input: Write a function to find the GCD of two given numbers using the Euclidean algorithm. The function should return the GCD of the two numbers. If the second number is 0, the function should return the first number.
  assert findGCD(1000, 500)==500
  assert findGCD(29, 3)==1
  assert findGCD(4, 16)==4
  assert findGCD(0, 10)==10
  assert findGCD(8, 0)==8
output: def findGCD(a, b):
      while b != 0:
          a, b = b, a % b
      return a