Balanced Parenthesis // python data-structures

Question

def balanced(l):
s=[]
for i in l:
if i == "(":
s.insert(0,i)
elif i ==")":
if s==[] : return False
s.pop(0)
return s==[]

print(balanced(input()))

----------------------------------------

def balanced(l):
if l.find('(') > l.find(')') :
return False
s = []
for i in l :
if i == '(' :
s.insert(0, i)
elif i == ')' :
s.pop(0)
return s==[]
print(balanced(input()))

Why this two codes are not gave same results for test case #7 ???

Answer 1

Hirani Pranav ,

the second code crashes if input is e.g.: (()(()))))

▪︎the first code checks for an empty list with:

if s==[] : return False
▪︎the second code is not doing this check and ends up with an exception: < IndexError: pop from empty list >