[WEEK 03] valid palindrome

Author: sonjs7554

valid-palindrome/essaysir.java

@@ -0,0 +1,19 @@
+class Solution {
+    public boolean isPalindrome(String s) {
+        StringBuilder sb = new StringBuilder();
+        for (char c : s.toCharArray()) {
+            if (Character.isLetterOrDigit(c)) {
+                sb.append(Character.toLowerCase(c));
+            }
+        }
+
+        String result = sb.toString();
+        char[] x = result.toCharArray();
+        for (int i = 0; i < x.length / 2; i++) {
+            if (x[i] != x[x.length - i - 1]) {
+                return false;
+            }
+        }
+        return true;
+    }
+}