动态规划_斐波那契数列

class Solution(object):


    def zhuhanshu(self,n):
        self.count = 0
        self.memo = [-1 for i in range(n+1)]


    def fib1(self,n):
        if n == 0 or n == 1:
            return 1
        else:
            return self.fib(n-1)+self.fib(n-2)



    # 记忆化搜索
    def fib2(self,n):

        self.count += 1

        if n == 1 or n == 0:
            return 1


        if self.memo[n] == -1:
            self.memo[n] = self.fib2(n-1)+self.fib2(n-2)
        return self.memo[n]


    def fib2(self,n):
        memo = [-1 for i in range(n+1)]

        memo[0] = 1
        memo[1] = 1

        for i in range(2,n+1):
            memo[i] = memo[i-1] + memo[i-2]
        return memo[n]