Create 590. N-ary Tree Postorder Traversal

Author: Chayandas07

590. N-ary Tree Postorder Traversal

@@ -0,0 +1,22 @@
+class Solution {
+public:
+    vector<int> ans;
+
+    void solve(Node* root) {
+        if (root == 0) {
+            return;
+        }
+
+        for (const auto& node : root->children) {
+            solve(node);
+        }
+
+        ans.push_back(root->val);
+        return;
+    }
+
+    vector<int> postorder(Node* root) {
+        solve(root);
+        return ans;
+    }
+};