fibonacci python example

Example 1: fibonacci sequence python

# WARNING: this program assumes the
# fibonacci sequence starts at 1
def fib(num):
	"""return the number at index `num` in the fibonacci sequence"""
    if num <= 2:
        return 1
    return fib(num - 1) + fib(num - 2)

# method 2: use `for` loop
def fib2(num):
	a, b = 1, 1
	for _ in range(num - 1):
		a, b = b, a + b
	return a


print(fib(6))  # 8
print(fib2(6))  # same result, but much faster

Example 2: fibonacci python

# Implement the fibonacci sequence
	# (0, 1, 1, 2, 3, 5, 8, 13, etc...)
	def fib(n):
		if n== 0 or n== 1:
			return n
		return fib (n- 1) + fib (n- 2)