## Backspace String Compare

Solution (build string ❌) Time: O(N) Space: O(N) class Solution: def backspaceCompare(self, S: str, T: str) -> bool: res_1 = self.helper(S) res_2 = self.helper(T) return len(res_1) == len(res_2) and res_1 == res_2 def helper(self, s): stack = [] for c in s: if c != "#": stack.append(c) else: if len(stack) > 0: stack.pop() return "".join(stack) s Solution (two pointers 👍🏼) Time: O(N) Space: O(1) from itertools import zip_longest class Solution: def backspaceCompare(self, S: str, T: str) -> bool: return all( a == b for a, b in zip_longest(self.