剑指 Offer-JZ60-把二叉树打印成多行

题目描述

从上到下按层打印二叉树，同一层结点从左至右输出。每一层输出一行。

解题思路

59题都会做了，60题不可能不会！(*^▽^*)

代码实现

/*
struct TreeNode {
    int val;
    struct TreeNode *left;
    struct TreeNode *right;
    TreeNode(int x) :
            val(x), left(NULL), right(NULL) {
    }
};
*/
class Solution {
public:
        vector<vector<int> > Print(TreeNode* pRoot) {
            vector<vector<int>> printContent;
            if(pRoot == NULL) return printContent;
            
            queue<TreeNode *> q;
            
            q.push(pRoot);
            while(!q.empty()){
                vector<int> v;
                
                int curQueueSize = q.size();
                for(int i = 0; i < curQueueSize; i++){
                    TreeNode *queueFrontElem = q.front();
                    v.push_back(queueFrontElem->val);
                    q.pop();
                    if(queueFrontElem->left) q.push(queueFrontElem->left);
                    if(queueFrontElem->right) q.push(queueFrontElem->right);
                }
                printContent.push_back(v);
            }
            
            return printContent;
        }
    
};

运行结果

运行时间：5ms
占用内存：504k