python使用list实现栈
# -*- coding: utf-8 -*-
"""
@author: sato
@file: stack.py
@time: 2019-08-22 00:06
"""
class Stack(object):
def __init__(self):
self.items = []
def is_empty(self):
return len(self.items) == 0
def push(self, item):
self.items.append(item)
def pop(self):
if not self.is_empty():
return self.items.pop()
raise IndexError('Stack is empty!')
def len(self):
return len(self.items)
def peek(self):
return self.items[len(self.items) - 1]
# s = Stack()
# print(s.is_empty())
# print(s.pop())
def reverse_str(mystr):
# 反转字符串
output = ''
s = Stack()
for m in mystr:
s.push(m)
while not s.is_empty():
output += s.pop()
# print(output)
def is_balanced(symbolstring):
# 利用栈, 判断括号的平衡性
s = Stack()
balanced = True
for i in symbolstring:
# print(i)
if i not in ')]}([{':
continue
if balanced:
if i in '([{':
s.push(i)
else:
if s.is_empty():
return False
else:
# print(s.pop(), i)
if ')]}'.index(i) != '([{'.index(s.pop()):
return False
else:
return balanced
return s.is_empty() and balanced
def Dec2Bin(decNumber):
# 利用栈十进制转换为二进制
s = Stack()
while decNumber > 0:
temp = decNumber % 2
s.push(temp)
decNumber = decNumber // 2
binString = ''
while not s.is_empty():
binString += str(s.pop())
print(binString)
# Dec2Bin(9)
# 利用栈实现多进制转换 十进制转换为多进制
def any_converter(decNumber, base):
digits = '0123456789ABCDEF'
s = Stack()
while decNumber > 0:
temp = decNumber % base
s.push(temp)
decNumber = decNumber // base
new_string = ''
while not s.is_empty():
new_string += digits[s.pop()]
print(new_string)
any_converter(15, 16)