题解 | #求二叉树的层序遍历#
求二叉树的层序遍历
https://www.nowcoder.com/practice/04a5560e43e24e9db4595865dc9c63a3
/** * struct TreeNode { * int val; * struct TreeNode *left; * struct TreeNode *right; * }; */ class Solution { public: /** * * @param root TreeNode类 * @return int整型vector<vector<>> */ vector<vector<int> > levelOrder(TreeNode* root) { vector<vector<int> >res; if(root==nullptr)return res; queue<TreeNode *>q; q.push(root); TreeNode *cur; while(!q.empty()){ vector<int> row; int n=q.size(); for(int i=0;i<n;++i){ cur=q.front(); q.pop(); row.push_back(cur->val); if(cur->left){ q.push(cur->left); } if(cur->right){ q.push(cur->right); } } res.push_back(row); } return res; // write code here } };
/** * struct TreeNode { * int val; * struct TreeNode *left; * struct TreeNode *right; * }; */ class Solution { public: /** * * @param root TreeNode类 * @return int整型vector<vector<>> */ vector<vector<int> > levelOrder(TreeNode* root) { vector<vector<int> >res; if(root==nullptr)return res; queue<TreeNode *>q; q.push(root); TreeNode *cur; while(!q.empty()){ vector<int> row; int n=q.size(); for(int i=0;i<n;++i){ cur=q.front(); q.pop(); row.push_back(cur->val); if(cur->left){ q.push(cur->left); } if(cur->right){ q.push(cur->right); } } res.push_back(row); } return res; // write code here } };