剑指Offer 30 包含min函数的栈

包含min函数的栈

定义栈的数据结构，请在该类型中实现一个能够得到栈中所含最小元素的min函数（时间复杂度应为O（1））。

# -*- coding:utf-8 -*-
class Solution:
    def __init__(self):
        self.stack = []
        self.list = []
        
    def push(self, node):
        self.stack.append(node)
        self.list.append(node)
        self.list = sorted(self.list)
        # write code here
    def pop(self):
        r = self.stack.pop(-1)
        self.list.remove(r)
        return r
        # write code here
    def top(self):
        r = self.stack[-1]
        return r
        # write code here
    def min(self):
        r = self.list[0]
        return r
        # write code here