把二叉树打印成多行

题目描述

从上到下按层打印二叉树，同一层结点从左至右输出。每一层输出一行。

/*
struct TreeNode {
    int val;
    struct TreeNode *left;
    struct TreeNode *right;
    TreeNode(int x) :
            val(x), left(NULL), right(NULL) {
    }
};
*/
class Solution {
public:
vector<vector<int> > Print(TreeNode* pRoot) {
	vector<vector<int>> ans;
	vector<int> flag;

	if(!pRoot)
		return ans;

	queue<TreeNode*> temp;
	queue<TreeNode*> tempPlus;
	temp.push(pRoot);

	while(!temp.empty())
	{
		TreeNode* cur = temp.front();
		flag.push_back(cur->val);
		temp.pop();

		if(cur->left)
			tempPlus.push(cur->left);
		if(cur->right)
			tempPlus.push(cur->right);

		if(temp.empty())
		{
			temp = tempPlus;
            queue<TreeNode*> odd;
			tempPlus = odd;
			ans.push_back(flag);
			flag.clear();
		}
	} 
	
	return ans;
}
    
};