Merge pull request neetcode-gh#1946 from thuanle123/680-valid-palindr…

…ome-ii

create 680. Valid Palindrome II c#

csharp/0680-valid-palindrome-ii.cs

@@ -0,0 +1,31 @@
+public class Solution
+{
+ public bool ValidPalindrome(string s)
+ {
+ int leftPointer = 0;
+ int rightPointer = s.Length - 1;
+ while (leftPointer < rightPointer)
+ {
+ if (s[leftPointer] != s[rightPointer])
+ {
+ return IsPalindrome(s, leftPointer + 1, rightPointer) || IsPalindrome(s, leftPointer, rightPointer - 1);
+ }
+ leftPointer++;
+ rightPointer--;
+ }
+ return true;
+ }
+ public bool IsPalindrome(String s, int leftPointer, int rightPointer)
+ {
+ while (leftPointer < rightPointer)
+ {
+ if (s[leftPointer] != s[rightPointer])
+ {
+ return false;
+ }
+ leftPointer++;
+ rightPointer--;
+ }
+ return true;
+ }
+}