Day 105

Kth Smallest Element In Tree.java

@@ -0,0 +1,30 @@
+/**
+ * Definition for binary tree
+ * class TreeNode {
+ *     int val;
+ *     TreeNode left;
+ *     TreeNode right;
+ *     TreeNode(int x) {
+ *      val = x;
+ *      left=null;
+ *      right=null;
+ *     }
+ * }
+ */
+public class Solution {
+    public int kthsmallest(TreeNode A, int B) {
+        Queue<TreeNode> q = new ArrayDeque<>();
+        ArrayList<Integer> ans = new ArrayList<>();
+        q.add(A);
+        while(!q.isEmpty()){
+            TreeNode curr = q.poll();
+            ans.add(curr.val);
+            if(curr.left != null) 
+                q.add(curr.left);
+            if(curr.right != null) 
+                q.add(curr.right);
+        }
+        Collections.sort(ans);
+        return ans.get(B-1);
+    }
+}