# -*- coding:utf-8 -*-
class Solution:
    def __init__(self):
        self.stack = []
        self.minv = None
    def push(self, node):
        # write code here
        self.stack.append(node)
    def pop(self):
        # write code here
        self.stack.pop()
    def top(self):
        # write code here
        return self.stack[-1]
    def min(self):
        # write code here
        return min(self.stack)

这样的时间复杂度是O(n)不满足要求,看了下题解,在new一个list存最小值即可。