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Check if a String Is a Palindrome
Normalize the input (lowercase + strip non-alphanumerics) and check if it reads the same forwards and backwards using two pointers. Complexity: O(n) time, O(n) space for normalization (O(1) extra possible).
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Check if a String Is a Palindrome: Normalize the input (lowercase + strip non-alphanumerics) and check if it reads the same forwards and backwards using two pointers. Complexity: O(n) time, O(n)…. Expect strings and iteration decisions under easy level constraints.
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