LeetCode 103. 二叉树的锯齿形层序遍历
原题链接
中等
作者:
我是java同学
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2024-02-16 13:45:47
,
所有人可见
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阅读 34
/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode() : val(0), left(nullptr), right(nullptr) {}
* TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
* TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
* };
*/
class Solution {
public:
vector<vector<int>> zigzagLevelOrder(TreeNode* root) {
vector<vector<int>> res;
if (!root) return res;
queue<TreeNode*> q;
q.push(root);
bool flag = true;
while (q.size()) {
int t = q.size();
vector<int> path;
while (t -- ) {
auto t = q.front();
q.pop();
path.push_back(t->val);
if (t->left) q.push(t->left);
if (t->right) q.push(t->right);
}
if (flag == false) reverse(path.begin(), path.end());
flag = !flag;
res.push_back(path);
}
return res;
}
};