refactor 255

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_255.java

@@ -2,29 +2,23 @@
 
 import java.util.Stack;
 
-/**
- * 255. Verify Preorder Sequence in Binary Search Tree
- * Given an array of numbers, verify whether it is the correct preorder traversal sequence of a binary search tree.
- * You may assume each number in the sequence is unique.
-
- Follow up:
- Could you do it using only constant space complexity?
- */
 public class _255 {
 
-    public boolean verifyPreorder(int[] preorder) {
-        int low = Integer.MIN_VALUE;
-        Stack<Integer> stack = new Stack();
-        for (int p : preorder) {
-            if (p < low) {
-                return false;
-            }
-            while (!stack.empty() && p > stack.peek()) {
-                low = stack.pop();
+    public static class Solution1 {
+        public boolean verifyPreorder(int[] preorder) {
+            int low = Integer.MIN_VALUE;
+            Stack<Integer> stack = new Stack();
+            for (int p : preorder) {
+                if (p < low) {
+                    return false;
+                }
+                while (!stack.empty() && p > stack.peek()) {
+                    low = stack.pop();
+                }
+                stack.push(p);
             }
-            stack.push(p);
+            return true;
         }
-        return true;
     }
 
 }