Valid_Palindrome

Leetcode/Leetcode_August_Challenge/Valid_Palindrome.java

@@ -0,0 +1,38 @@
+package Leetcode_August_Challenge;
+
+public class Valid_Palindrome {
+
+ public boolean isPalindrome(String s) {
+
+ if(s==null){
+ return false;
+ }
+
+ s = s.toLowerCase();
+
+ int i=0;
+ int j=s.length()-1;
+
+ while(i<j){
+ while(i<j && !((s.charAt(i)>='a' && s.charAt(i)<='z') 
+ || (s.charAt(i)>='0'&&s.charAt(i)<='9'))){
+ i++;
+ }
+
+ while(i<j && !((s.charAt(j)>='a' && s.charAt(j)<='z') 
+ || (s.charAt(j)>='0'&&s.charAt(j)<='9'))){
+ j--;
+ }
+
+ if(s.charAt(i) != s.charAt(j)){
+ return false;
+ }
+
+ i++;
+ j--;
+ }
+
+ return true;
+
+ }
+}