Fibonacci_memoized

def fib(num, memo):
    if memo == []:
        memo = [None for _ in range(num+1)]
    
    if num == 0:
        result = 0
    elif num == 1 or num == 2:
        result = 1
    elif memo[num] != None:
        result = memo[num]
    else:
        result = fib(num-1, memo) + fib(num-2, memo)
    
    memo[num] = result
    return result

print("Hello World!")

memo = []
sample1 = 5
result1 = fib(sample1, memo)
print(f"result1: {result1}")
assert(result1 == 5)

memo = []
sample2 = 7
result2 = fib(sample2, memo)
print(f"result2: {result2}")
assert(result2 == 13)

memo = []
sample3 = 9
result3 = fib(sample3, memo)
print(f"result3: {result3}")
assert(result3 == 34)

print("good bye world")