二叉树层序遍历 之字形遍历问题
简单写一下初级的层序遍历和进阶版层序遍历
void rightSideView(TreeNode* root) {
queue<TreeNode*> q;
q.push(root);
while (!q.empty())
{
TreeNode* tmp = q.front();
cout<<"cur val is "<<tmp->val<<endl;
q.pop();
if(tmp->left != NULL) q.push(tmp->left);
if(tmp->right != NULL) q.push(tmp->right);
}
} //20_1117 临时贴一个二叉树层序遍历进阶版(每一层保存在一个数组中，最终是一个二维数组)
vector<vector<int>> getTreeNodeFloorPrint(TreeNode* root)
{
vector<vector<int>> res;
if(root == NULL) return res;
queue<TreeNode*> q;
q.push(root);
while (!q.empty())
{
int count = 0;
int qSize = q.size();
vector<int> tmp;
while (count < qSize)
{
TreeNode* cur = q.front();
q.pop();
tmp.push_back(cur->val);
if(cur->left != NULL) q.push(cur->left);
if(cur->right != NULL) q.push(cur->right);
count++;
}
res.push_back(tmp);
}
return res;
} 