题解 | #斐波那契数列# -- [Python3]

class Solution:
    def Fibonacci(self, n):
        pre1 = 0
        pre2 = 1
        if n == 0 :
            return pre1
        if n == 1:
            return pre2
        n = n - 1
        while n:
            n = n - 1;
            temp = pre1
            pre1 = pre2
            pre2 = temp+pre2
        return pre2