Algorithms

Palindrome Check

easyalgorithmsstringtwo-pointers
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Problem

Given a string, return `true` if it is a palindrome considering only alphanumeric characters (case-insensitive). Otherwise return `false`.

Your solution
Test results
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About this challenge

Palindrome Check is a easy algorithms coding challenge. It tests algorithmic thinking and complexity analysis — the kind of problem-solving that shows up constantly in technical interviews. Write your solution in the editor above, run it against the test cases, and get instant feedback — free, in your browser, no sign-up.

Show a hint & approach (spoiler)

Hint: Normalize to lowercase alphanumerics, then compare against its reverse OR use two pointers.

Keep practicing

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