Python Data Structures: Balanced Parentheses help

Question

I am making a few different solutions for the last project in python data structures and this is one of them.
It works for 6 out of the 7 tests, and I can’t understand why it doesn’t work on the last.
Here is my code:

def balanced(expression):
out1 = 0
for i in expression:
if i == '(':
out1 +=1
elif i == ')':
out1 -= 1
if out1 == 0:
return True
else:
return False

print(balanced(input()))

Answer 1

There are several ways to take care of this issue. A simple way would be to return False if out1 is negative at any point.
But if I remember correctly the task says you should use a stack.

Answer 2

I have found a different solution using a three strings which works. Thank you for your help.

Answer 3

Your code only checks whether the number of opening and closing parentheses are the same. It does not check sequence. So for the following it shows True instead of false:
)1 (

Answer 4

Aleksei Radchenkov I know. I wrote "Your code only checks ...". Which is the reason it doesn't pass the test case.

Answer 5

Simon Sauter, oh right, I misread your comment, sorry... 😉

Answer 6

No problem.

Answer 7

ubai no, not even close.

Answer 8

Simon Sauter, actually it does check sequence (test 7), I have just solved it, and it does require to check if there is ')' but no '(' even if there are equal amount of them.

Answer 9

Magnus4791, So your code is very near. What you need to add, is to return False if "out" is negative at any point.

Here is code that functions correctly(variable names are changed) :

https://code.sololearn.com/cH15IFewR82T/?ref=app

Answer 10

balanced = lambda x :x =='(' or x == ')'

Answer 11

balanced = lambda x :x =='(' or x == ')'

This is your answer. 💯