原题
实现一个栈，可以使用除了栈之外的数据结构
样例
push(1)
pop()
push(2)
top() // return 2
pop()
isEmpty() // return true
push(3)
isEmpty() // return false
解题思路
- 使用python list实现stack数据结构
完整代码
class Stack:
# initialize your data structure here.
def __init__(self):
self.items = []
# @param x, an integer, push a new item into the stack
# @return nothing
def push(self, x):
# Write your code here
self.items.append(x)
# @return nothing, pop the top of the stack
def pop(self):
# Write your code here
self.items.pop()
# @return an integer, return the top of the stack
def top(self):
# Write your code here
return self.items[-1]
# @return a boolean, check the stack is empty or not.
def isEmpty(self):
# Write your code here
return len(self.items) == 0
