Day10

145. Binary Tree Postorder Traversal/Solution.cs

@@ -0,0 +1,24 @@
+namespace _145._Binary_Tree_Postorder_Traversal;
+
+public class Solution
+{
+    public IList<int> PostorderTraversal(TreeNode root)
+    {
+        var result = new List<int>();
+        if (root == null) return result;
+        var stack = new Stack<TreeNode>();
+        stack.Push(root);
+        while (stack.Any())
+        {
+            var cur = stack.Pop();
+            result.Add(cur.val);
+            if (cur.left != null)
+                stack.Push(cur.left);
+            if (cur.right != null)
+                stack.Push(cur.right);
+        }
+        result.Reverse();
+
+        return result;
+    }
+}