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Valid Palindrome II

easy

Solution write-up

stringTime: O(n)Space: O(1)Frequency: 4

Given a string, determine if it can be a palindrome after deleting at most one character.

Example 1:

Input: s = "aba"
Output: true

Example 2:

Input: s = "abca"
Output: true
Explanation: Removing 'b' or 'c' yields a palindrome.

Example 3:

Input: s = "abc"
Output: false

two-pointers

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stringTime: O(n)Space: O(1)Frequency: 4

Given a string, determine if it can be a palindrome after deleting at most one character.

Example 1:

Input: s = "aba"
Output: true

Example 2:

Input: s = "abca"
Output: true
Explanation: Removing 'b' or 'c' yields a palindrome.

Example 3:

Input: s = "abc"
Output: false

two-pointers