Write a function that takes a string, s, as an input and determines whether or not it is a palindrome.

Note: A palindrome is a word, phrase, or sequence of characters that reads the same backward as forward.


  • 11 \leq s.length 2×105\leq 2 \times 10^5
  • The string s will not contain any white space and will only consist of ASCII characters(digits and letters).


Understand the problem

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Valid Palindrome


“abab” is a palindrome.





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Implement your solution in the following coding playground. The supporting code template provided in two_pointers.js is meant to assist in developing your solution to the problem.

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usercode > main.js
function isPalindrome(s) {
// Replace this placeholder return statement with your code
return false;
export { isPalindrome };
Valid Palindrome