斐波那契數列的遞歸和非遞歸實現 —— python

# -*- coding:utf-8 -*-
#遞歸實現
def Fibonacci(n):
    if n <= 1:
        return n
    return (Fibonacci(n-1) + Fibonacci(n-2))

#非遞歸實現
class Solution:
    def Fibonacci(self, n):
        a = [0,1]
        if n<2:
            return a[n]
        for i in range(2,n+1):
            a.append(a[i-1]+a[i-2])
        return a[n]