33 lines
851 B
C++
33 lines
851 B
C++
#include <vector>
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#include <functional>
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// Definition for a Node.
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class Node {
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public:
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int val;
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std::vector<Node*> children;
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Node(int _val, std::vector<Node*> _children) : val(_val), children(std::move(_children)) {}
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};
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/**
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* 589. N-ary Tree Preorder Traversal
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* Given the root of an n-ary tree, return the preorder traversal of its nodes' values.
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* Nary-Tree input serialization is represented in their level order traversal. Each group of children is separated by the null value (See examples)
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*/
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class Solution {
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public:
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static std::vector<int> preorder(Node* root) {
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std::vector<int> ret;
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std::function<void(const Node* const)> traverse = [&](const Node* const ptr) {
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if (!ptr) return;
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ret.push_back(ptr->val);
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for (const Node* const i : ptr->children)
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traverse(i);
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};
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traverse(root);
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return ret;
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}
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};
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