#Leetcode# 103. Binary Tree Zigzag Level Order Traversal
发布时间:2020-12-14 04:26:59 所属栏目:大数据 来源:网络整理
导读:https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/ ? Given a binary tree,return the? zigzag level order ?traversal of its nodes‘ values. (ie,from left to right,then right to left for the next level and alternate betwe
https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/ ? Given a binary tree,return the?zigzag level order?traversal of its nodes‘ values. (ie,from left to right,then right to left for the next level and alternate between). For example: 3 / 9 20 / 15 7 ? return its zigzag level order traversal as: [ [3],[20,9],[15,7] ] 代码: /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x),left(NULL),right(NULL) {} * }; */ class Solution { public: vector<vector<int>> zigzagLevelOrder(TreeNode* root) { vector<vector<int> > ans; if(!root) return ans; level(root,ans,1); for(int i = 0; i < ans.size(); i ++) { if(i % 2) { for(int j = 0; j < ans[i].size() / 2; j ++) swap(ans[i][j],ans[i][ans[i].size() - j - 1]); } } return ans; } void level(TreeNode* root,vector<vector<int> >& ans,int depth) { vector<int> v; if(depth > ans.size()) { ans.push_back(v); v.clear(); } ans[depth - 1].push_back(root -> val); if(root -> left) level(root -> left,depth + 1); if(root -> right) level(root -> right,depth + 1); } }; (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |