Valid Palindrome II

Problem

Given a string s, return true if it can become a palindrome after deleting at most one character.

Example

s = "abca"
Output: true  // delete 'c'

Constraints

• 1 ≤ s.length ≤ 10^5
• Lowercase English letters

Approach

Two pointers; on first mismatch, try skipping the left or the right character. O(n).