从上往下打印二叉树

题目描述

/*
struct TreeNode {
int val;
struct TreeNode *left;
struct TreeNode *right;
TreeNode(int x) :
val(x), left(NULL), right(NULL) {
}
};*/
class Solution {
public:
vector<int> PrintFromTopToBottom(TreeNode *root) {
vector<int> vv;
if (root == NULL)
return vv;
std::queue<TreeNode *> qq;
qq.push(root);
TreeNode *tem;
while(!qq.empty())
{
tem = qq.front();
qq.pop();
vv.push_back(tem->val);
if (tem ->left != NULL)
qq.push(tem->left);
if(tem ->right != NULL)
qq.push(tem->right);
}
return vv;
}
};