剑指offer 面试题23 按层遍历二叉树

struct BinaryTreeNode{
int data;
BinaryTreeNode *left;
BinaryTreeNode *right;
};
void PrintTreeInLayerOrder(BinaryTreeNode *pRoot){
if(pRoot==NULL) return;
std::deque<BinaryTreeNode*> TreeNodeDeque;
TreeNodeDeque.push_back(pRoot);
while(!TreeNodeDeque.empty()){
BinaryTreeNode *pNode=TreeNodeDeque.front();
TreeNodeDeque.pop_front();
cout<<pNode->data;
if(pNode->left)
TreeNodeDeque.push_back(pNode->left);
if(pNode->right)
TreeNodeDeque.push_back(pNode->right);
}
}