class Pin():
def __init__(self, name):
self.stack = Stack()
self.label = name
def name(self):
return self.label
def isEmpty(self):
return self.stack.isEmpty()
def check(self, d):
return self.stack.isEmpty() or d.get() < self.stack.peek().get()
def peek(self):
return self.stack.peek()
def push(self, d):
if self.check(d):
self.stack.push(d)
return True
else:
return False
def pop(self):
return self.stack.pop()
def __str__(self):
return self.name() + "=>" + str(self.stack)
def infixTopostfix(infix):
prec = {"*": 3, "/": 3, "+": 2, "-": 2, "(": 1, ")": 1}
opstack = Stack()
postfixlist = []
infixlist = infix.split()
for token in infixlist:
if token in "ABCDEFGHIJKLMNOPQRSTUVWXYZ" or token in "0123456789":
postfixlist.append(token)
elif token == "(":
opstack.push(token)
elif token == ")":
toptoken = opstack.pop()
while toptoken != "(":
postfixlist.append(toptoken)
toptoken = opstack.pop()
else:
while (not opstack.isEmpty()
) and prec[opstack.peek()] >= prec[token]:
postfixlist.append(opstack.pop())
opstack.push(token)
while not opstack.isEmpty():
postfixlist.append(opstack.pop())
return " ".join(postfixlist)
def infixToPostfit(infiexpr):
prec = {}
prec['*'] = 3
prec['/'] = 3
prec['+'] = 2
prec['-'] = 2
prec['('] = 1
opStack = Stack()
postfitList = []
tokenList = infiexpr.split()
print(tokenList)
for token in tokenList:
if token in "ABCDEFG" or token in "0123456789":
postfitList.append(token)
elif token == '(':
opStack.push(token)
elif token == ')':
topToken = opStack.pop()
while topToken != '(':
postfitList.append(topToken)
topToken = opStack.pop()
else:
while (not opStack.isEmpty()) and (prec[opStack.peek()] >=
prec[token]):
postfitList.append(opStack.pop())
opStack.push(token)
while not opStack.isEmpty():
postfitList.append(opStack.pop())
return " ".join(postfitList)
def xiaoxiaole(strings):
s = Stack()
list = []
for str in strings: # 如果与栈顶相同则消去栈顶， 不同则压入栈顶
if str == s.peek():
s.remove()
else:
s.push(str)
if s.isEmpty():
return None
else:
while not s.isEmpty():
list.insert(0, s.pop()) # 取出栈中的每个元素，注意排列顺序
return "".join(list)
import sys
sys.path.append('../')
from basic.stack import Stack
s = Stack()
print(s.isEmpty())
s.push(4)
s.push('dog')
print(s.peek())
s.push(True)
print(s.size())
print(s.isEmpty())
s.push(8.4)
print(s.pop())
print(s.pop())
print(s.size())