How do I create a program using stack to check balanced parenthesis in an expression?

Question

https://photos.app.goo.gl/r4zKHpTGwoVHMVzW9

Answer 1

Iterate through expression.
If u find ( , push to stack.
If you find ) pop from stack.

If stack is empty although u find ) => not balanced
If stack is not empty at end of expression => not balanced

Answer 2

Thanks let me try

Answer 3

What a question?

Answer 4

Check the link for more info

Answer 5

Ask Chatgpt it should know the answer.

Answer 6

You can create a program using a stack to check if an expression has balanced parentheses by following these steps:

Create an empty stack to store opening parentheses.
Iterate through each character in the expression.
If the current character is an opening parenthesis (i.e., (, {, or [), push it onto the stack.
If the current character is a closing parenthesis (i.e., ), }, or ]), check if the stack is empty. If the stack is empty, the expression is not balanced (i.e., there is a closing parenthesis with no matching opening parenthesis). If the stack is not empty, pop the top element from the stack and compare it with the current closing parenthesis. If they don't match (i.e., the current closing parenthesis does not match the most recent opening parenthesis), the expression is not balanced.
If you reach the end of the expression and the stack is empty, the expression is balanced. Otherwise, it is not balanced.

def is_balanced(expr):
stack = []
for char in expr:
if char in ['(', '{', '[']:
stack.append(char)
elif char in [')', '}', ']']:
if not stack:
return False
top = stack.pop()
if (top == '(' and char != ')') or (top == '{' and char != '}') or (top == '[' and char != ']'):
return False
return not stack

# Example usage:
expr = input("Enter an expression: ")
if is_balanced(expr):
print("The expression is balanced.")
else:
print("The expression is not balanced.")