从上往下打印二叉树(算法）

题目描述

vector<int> PrintFromTopToBottom(TreeNode *root) {

queue<TreeNode*> qList;
vector<int> vData;
if(root == NULL) return vData;
qList.push(root);

while(!qList.empty())
{
TreeNode* pNode = qList.front();
qList.pop();
vData.push_back(pNode->val);
if(pNode->left != NULL)
qList.push(pNode->left);
if(pNode->right != NULL)
qList.push(pNode->right);
}
return vData;
}