Given an n-ary tree, return the postorder traversal of its nodes' values.
For example, given a 3-ary tree:
Return its postorder traversal as: [5,6,3,2,4,1].
Note:
Recursive solution is trivial, could you do it iteratively?
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和leetcode589. N-ary Tree Preorder Traversal类似。用递归会简单些
C++代码：
/*
// Definition for a Node.
class Node {
public:
int val;
vector<Node*> children; Node() {} Node(int _val, vector<Node*> _children) {
val = _val;
children = _children;
}
};
*/
class Solution {
public:
vector<int> postorder(Node* root) {
vector<int> vec;
helper(root,vec);
return vec;
}
void helper(Node* root,vector<int> &vec){
if(!root) return;
for(Node *cur:root->children){
helper(cur,vec);
}
vec.push_back(root->val);
}
};