same-tree solution

Author: chjung99

same-tree/chjung99.java

@@ -0,0 +1,48 @@
+import java.util.*;
+
+/**
+ * Definition for a binary tree node.
+ * public class TreeNode {
+ *     int val;
+ *     TreeNode left;
+ *     TreeNode right;
+ *     TreeNode() {}
+ *     TreeNode(int val) { this.val = val; }
+ *     TreeNode(int val, TreeNode left, TreeNode right) {
+ *         this.val = val;
+ *         this.left = left;
+ *         this.right = right;
+ *     }
+ * }
+ */
+class Solution {
+    final int NULL_MARKER = Integer.MIN_VALUE;
+    public boolean isSameTree(TreeNode p, TreeNode q) {
+        Queue<Integer> OrderP = new ArrayDeque<>();
+        Queue<Integer> OrderQ = new ArrayDeque<>();
+        trevasalTree(p, OrderP);
+        trevasalTree(q, OrderQ);
+
+        if (OrderP.size() != OrderQ.size()) return false;
+
+        while (!OrderP.isEmpty() && !OrderQ.isEmpty()){
+            Integer a = OrderP.poll();
+            Integer b = OrderQ.poll();
+            if (!a.equals(b)) return false;
+        }
+
+        return OrderP.isEmpty() && OrderQ.isEmpty();
+    }
+    public void trevasalTree(TreeNode t, Queue<Integer> queue){
+        // System.out.print(t.val+ " ");
+        if (t == null){
+            queue.add(NULL_MARKER);
+            return;
+        }
+        queue.add(t.val);
+        trevasalTree(t.left, queue);
+        trevasalTree(t.right, queue);
+
+    }
+}
+