题目
剑指 Offer 32 - I. 从上到下打印二叉树
我的思路
层序遍历,借助队列实现
我的实现
/** * 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<int> levelOrder(TreeNode* root) { queue<TreeNode *> Q; vector<int> result; if(root==nullptr)return result; Q.push(root); while(!Q.empty()){ TreeNode *tempRoot = Q.front(); Q.pop(); result.push_back(tempRoot->val); if(tempRoot->left!=NULL)Q.push(tempRoot->left); if(tempRoot->right!=NULL)Q.push(tempRoot->right); } return result; } }; /* 层序遍历 借助队列实现 */