590. N-ary Tree Postorder Traversal

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Question Given the root of an n-ary tree, return the postorder traversal of its nodes' values. Nary-Tree input serialization is represented in their level order traversal. Each group of children is separated by the null value (See examples) Example 1: Input: root = [1,null,3,2,4,null,5,6] Output: [5,6,3,2,4,1] Example 2: Input: root = [1,null,2,3,4,5,null,null,6,7,null,8,null,9,10,null,null,11,null,12,null,13,null,null,14] Output: [2,6,14,11,7,3,12,8,4,13,9,10,5,1] Solution class Solution { public: vectorv; vector postorder(Node* root) { if(root==NULL) return v; for(int i=0;ichildren.size();i++){ postorder(root->children[i]); } v.push_back(root->val); return v; } };

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