"""
Solution for -> Valid Parentheses.
Created by Egor Kostan.
GitHub: https://github.com/ikostan
"""
[docs]
def valid_parentheses(string: str) -> bool:
"""
valid_parentheses function.
A function called that takes a string of parentheses,
and determines if the order of the parentheses is valid.
The function should return true if the string is valid,
and false if it's invalid.
:param string: str
:return: bool
"""
string = clean_up_string(string)
if string == "" or not string:
return True
if len(string) % 2 != 0:
return False
if string.count('(') != string.count(')'):
return False
string_list = list(s for s in string)
while string_list:
pair: bool = False
if string_list[0] == ')':
return False
for s in string_list[1:]:
if string_list[0] + s == '()':
del string_list[0]
string_list.remove(s)
pair = True
break
if not pair:
return False
return True
[docs]
def clean_up_string(string: str) -> str:
"""
Clean up string from invalid chars.
:param string: str
:return: str
"""
return ''.join(s for s in string if s in '()')