valid-palindrome solution

Author: toychip

valid-palindrome/toychip.java

@@ -0,0 +1,33 @@
+class Solution {
+    public boolean isPalindrome(String s) {
+        char[] charArray = s.toCharArray();
+        StringBuilder stringBuilder = new StringBuilder();
+
+        for (char c : charArray) {
+            if (Character.isLetterOrDigit(c)) {
+                stringBuilder.append(c);
+            }
+        }
+
+        String validChars = stringBuilder.toString();
+
+        char[] validArray = validChars.toCharArray();
+        char[] reversArray = new char[validArray.length];
+
+        for (int i = 0; i < validArray.length; i++) {
+            validArray[i] = Character.toLowerCase(validArray[i]);
+            reversArray[i] = Character.toLowerCase(reversArray[i]);
+        }
+
+        for (int i = 0; i < validArray.length; i++) {
+            reversArray[validArray.length - 1 - i] = validArray[i];
+        }
+
+        for (int i = 0; i < validArray.length; i++) {
+            if (reversArray[i] != validArray[i]) {
+                return false;
+            }
+        }
+        return true;
+    }
+}