680_ValidPalindromeII - a920604a/leetcode GitHub Wiki

---

title: 680. Valid Palindrome II categories: leetcode comments: false

problem

solution

class Solution {
public:
    bool isPalindrome(string s, int l, int r){
        while(l<r){
            if(s[l++]!=s[r--]) return false;
        }
        return true;
    }
    bool validPalindrome(string s) {
        
        int l=0, r=s.size()-1;
        while(l<r){
            if(s[l]!=s[r]) return isPalindrome(s, l+1,r) || isPalindrome(s, l,r-1);
            l++;
            r--;
        }
        return true;
    }
};

analysis

• time complexity O(n)
• space complexity O(1)