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最新推荐文章于 2025-01-03 15:16:25 发布

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最新推荐文章于 2025-01-03 15:16:25 发布

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# include <iostream>
#include<cstring>
#include<string>
#include<vector>
#include<cmath>
#include<queue>
using namespace std;

/*
struct TreeNode {
	int val;
	struct TreeNode *left;
	struct TreeNode *right;
	TreeNode(int x) :
			val(x), left(NULL), right(NULL) {
	}
};*/

class Solution {
public:
	queue<TreeNode*>Q;
    vector<int> PrintFromTopToBottom(TreeNode* root) {
		vector<int>res;
		if(root == nullptr)//!!!!判断参数合法性，不然提交一直错误
			return res;
		res.push_back (root->val);
		Q.push(root);
		while(!Q.empty())
		{
			TreeNode * temp = Q.front();
			Q.pop();
			if(temp->left)
			{
				res.push_back (temp->left->val);
				Q.push(temp->left);
			}
			if(temp->right)
			{
				res.push_back (temp->right->val);
				Q.push(temp->right);
			}

		}
		return res;


    }
};