def rev_word(string):
from Stack import ArrayStack # STACK IMPORTED FROM MY OWN COLLECTION
stack = ArrayStack() # ASSIGNING NEW STACK
reversedWords = "" # ASSIGNING NEW STRING, WILL BE ADDED REVERSED WORDS IN HERE LATER ON
word = "" #ASSIGNING NEW STRING, SO IT CAN ADD EACH WORD
#I AM ADDING A WHITE SPACE AT THE END OF THE STRING
#SO THE LOOP CAN UNDERSTAND THE END OF THE STRING
#IF I DONT ADD THIS, THE PROGRAM WILL NOT PUT THE LAST WORD IN THE STACK !
string = string + " "
for i in range(len(string)): #FOR EACH ELEMENT IN THE STRING
if string[i] != " ": #IF CHAR NOT A WHITE SPACE ADD CHARS TO THE WORD
word += string[i]
else:
if len(word) > 0: #IF THE LENGTH OF THE WORD MORE THAN ZERO
stack.push(word) #ADD WORD TO THE STACK
word = "" #CLEAR WORD VARIABLE, FOR THE NEXT ONE
for i in range(len(stack)):
reversedWords += stack.pop() + " " #ADDING EACH ELEMENT TO THE reversedWords STRING WITH SPACE BETWEEN WORDS
reversedWords = reversedWords[:-1] #REMOVING THE LAST ELEMENT OF THE STRING, BECAUSE IT IS A WHITE SPACE. ADDED FROM THE PREVIOUS LINE
return reversedWords
def is_html_matched(raw):
S = ArrayStack()
j = raw.find('<')
root = etree.Element("root")
curr = root
while j != -1:
k = raw.find('>', j + 1)
if k == -1:
return None
tag = raw[j + 1:k]
if tag.startswith('/'):
if S.is_empty():
return False
elif S.pop() != tag[1:]:
return False
curr = curr.getparent()
else:
curr = etree.SubElement(curr, tag)
S.push(tag)
j = raw.find('<', k + 1)
print(etree.tostring(root).decode('utf8'))
return S.is_empty()
def is_matched(expr):
left = '{(['
right = '})]'
S = ArrayStack()
for c in expr:
if c in left:
S.push(c)
elif c in right:
if S.is_empty():
return False
elif right.index(c) != left.index(S.pop()):
return False
return S.is_empty()
def balanced_expression(str_input):
stack = ArrayStack()
for i in str_input:
if i not in d:
stack.push(i)
else:
try:
output = stack.pop()
except:
return False
if output != d[i]:
return False
return stack.is_empty()
def balanced_expression(str_input):
d = {"}": "{", ")": "(", "]": "["}
stack = ArrayStack()
for i in str_input:
if i in "{[(":
stack.push(i)
else:
try:
out = stack.pop()
if out != d[i]:
return False
except:
return False
return stack.is_empty()
def is_matched_html(html_str):
lst = [i for i in get_tokens(html_str)]
stack = ArrayStack()
for i in lst:
if i[1] == "/":
try:
out = stack.pop()
if out[1:-1] != i[2:-1]:
return False
except:
return False
else:
stack.push(i)
return stack.is_empty()
def is_mathced_html(html_str):
stack = ArrayStack()
for i in get_tags(html_str):
if i[0] != "/":
stack.push(i)
else:
try:
val = stack.pop()
except:
return False
if i[1:] != val:
return False
return stack.is_empty()
def infixToPostfix(tokenList: list) -> list:
'''
Algoritms Architecture
1) 피연산자이면 그냥 출력
2) '('이면 스택에 push
3) ')' 이면 '('이 나올때 까지 스택에서 pop, 출력
4) 연산자이면 스택에서 이보다 높(거나 같)은 우선순위 것들을 pop, 출력
그리고 이 연산자는 스택에 push
5) 스택에 남아 있는 연산자는 모두 pop, 출력.
'''
prec = {
'*': 3, '/': 3,
'+': 2, '-': 2,
'(': 1,
}
opStack = Stack()
postfixList = []
for token in tokenList:
if type(token) is int:
postfixList.append(token)
else:
if opStack.isEmpty() and token in prec.keys():
opStack.push(token)
elif token == '(':
opStack.push(token)
elif token == ')':
while opStack.peek() != '(':
postfixList.append(opStack.pop())
opStack.pop()
elif prec.get(opStack.peek()) < prec.get(token):
opStack.push(token)
else:
postfixList.append(opStack.pop())
opStack.push(token)
while not opStack.isEmpty():
postfixList.append(opStack.pop())
return postfixList
def __init__(self):
self.stack = ArrayStack()
self.size = 0
class DupStack:
def __init__(self):
self.stack = ArrayStack()
self.size = 0
def __len__(self):
return len(self.size)
def is_empty(self):
return len(self) == 0
def push(self,e):
if self.is_empty():
self.stack.push((e,1))
else:
prev,dup = self.stack.top()
if prev == e:
self.stack.pop()
self.stack.push((prev,dup+1))
else:
self.stack.push((e,1))
self.size += 1
def top(self):
if self.is_empty():
raise Exception("Empty!!")
return self.stack.top()[0]
def top_dups_count(self):
if self.is_empty():
raise Exception("Empty!!")
return self.stack.top()[1]
def pop(self):
if self.is_empty():
raise Exception("Empty!!")
value,count = self.stack.top()
if count == 1:
return self.stack.pop()[0]
else:
self.stack.pop()
self.stack.push(value,count-1)
self.size -= 1
def pop_dups(self):
if self.is_empty():
raise Exception("Empty!!")
value,count = self.stack.pop()
self.size -= count
return value
def postfixEval(tokenList):
valStack = Stack()
for token in tokenList:
if type(token) is int:
valStack.push(token)
elif token == '*':
v1 = valStack.pop()
v2 = valStack.pop()
result = v2 * v1
valStack.push(result)
elif token == '/':
v1 = valStack.pop()
v2 = valStack.pop()
result = v2 / v1
valStack.push(result)
elif token == '+':
v1 = valStack.pop()
v2 = valStack.pop()
result = v2 + v1
valStack.push(result)
elif token == '-':
v1 = valStack.pop()
v2 = valStack.pop()
result = v2 - v1
valStack.push(result)
return valStack.pop()
def convert(S):
'''
materialize to ArrayStack
'''
opStack = ArrayStack()
answer = ''
for c in S:
if c not in "*/+-()":
answer += c
elif c == '(':
opStack.push(c)
elif c == ")":
while opStack.peek() != "(":
answer += opStack.pop()
opStack.pop()
elif (not opStack.isEmpty()) and prec.get(c) <= prec.get(
opStack.peek()):
answer += opStack.pop()
opStack.push(c)
else:
opStack.push(c)
while not opStack.isEmpty():
answer += opStack.pop()
return answer