++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

给定一个升序的数组,把他转换成一个高度平衡的二叉查找树

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Given an array where elements are sorted in ascending order, convert it to a height balanced BST.

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
递归的方法:
test.cpp:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
 
#include <iostream>
#include <cstdio>
#include <stack>
#include <vector>
#include "BinaryTree.h"

using namespace std;

/**
 * Definition for binary tree
 * struct TreeNode {
 * int val;
 * TreeNode *left;
 * TreeNode *right;
 * TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
TreeNode *tobst(vector<int> num, int begin, int end)
{

if(begin > end)
    {
        return NULL;
    }
    if(begin == end)
    {
        return new TreeNode(num[begin]);
    }
    int mid = begin + (end - begin) / 2;
    TreeNode *tmp = new TreeNode(num[mid]);
    tmp->left = tobst(num, begin, mid - 1);
    tmp->right = tobst(num, mid + 1, end);
    return tmp;
}

TreeNode *sortedArrayToBST(vector<int> &num)
{
    return tobst(num, 0, num.size() - 1);
}

vector<vector<int> > levelOrder(TreeNode *root)
{

vector<vector<int> > matrix;
    if(root == NULL)
    {
        return matrix;
    }
    vector<int> temp;
    temp.push_back(root->val);
    matrix.push_back(temp);

vector<TreeNode *> path;
    path.push_back(root);

int count = 1;
    while(!path.empty())
    {
        TreeNode *tn = path.front();
        if(tn->left)
        {
            path.push_back(tn->left);
        }
        if(tn->right)
        {
            path.push_back(tn->right);
        }
        path.erase(path.begin());
        count--;

if(count == 0)
        {
            vector<int> tmp;
            vector<TreeNode *>::iterator it = path.begin();
            for(; it != path.end(); ++it)
            {
                tmp.push_back((*it)->val);
            }
            if(tmp.size() > 0)
            {
                matrix.push_back(tmp);
            }
            count = path.size();
        }
    }
    return matrix;
}

// 树中结点含有分叉,
//                  4
//              /       \
//             2         6
//           /   \      /  \
//          1     3    5    7
int main()
{
    int arr[7] = {1, 2, 3, 4, 5, 6, 7};
    vector<int> num(arr, arr + 7);

TreeNode *root = sortedArrayToBST(num);

vector<vector<int> > ans = levelOrder(root);

for (int i = 0; i < ans.size(); ++i)
    {
        for (int j = 0; j < ans[i].size(); ++j)
        {
            cout << ans[i][j] << " ";
        }
    }
    cout << endl;
    DestroyTree(root);
    return 0;
}

结果输出:
4 2 6 1 3 5 7
BinaryTree.h:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
 
#ifndef _BINARY_TREE_H_
#define _BINARY_TREE_H_

struct TreeNode
{
    int val;
    TreeNode *left;
    TreeNode *right;
    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};

TreeNode *CreateBinaryTreeNode(int value);
void ConnectTreeNodes(TreeNode *pParent,
                      TreeNode *pLeft, TreeNode *pRight);
void PrintTreeNode(TreeNode *pNode);
void PrintTree(TreeNode *pRoot);
void DestroyTree(TreeNode *pRoot);

#endif /*_BINARY_TREE_H_*/

BinaryTree.cpp:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
 
#include <iostream>
#include <cstdio>
#include "BinaryTree.h"

using namespace std;

/**
 * Definition for binary tree
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */

//创建结点
TreeNode *CreateBinaryTreeNode(int value)
{
    TreeNode *pNode = new TreeNode(value);

return pNode;
}

//连接结点
void ConnectTreeNodes(TreeNode *pParent, TreeNode *pLeft, TreeNode *pRight)
{
    if(pParent != NULL)
    {
        pParent->left = pLeft;
        pParent->right = pRight;
    }
}

//打印节点内容以及左右子结点内容
void PrintTreeNode(TreeNode *pNode)
{
    if(pNode != NULL)
    {
        printf("value of this node is: %d\n", pNode->val);

if(pNode->left != NULL)
            printf("value of its left child is: %d.\n", pNode->left->val);
        else
            printf("left child is null.\n");

if(pNode->right != NULL)
            printf("value of its right child is: %d.\n", pNode->right->val);
        else
            printf("right child is null.\n");
    }
    else
    {
        printf("this node is null.\n");
    }

printf("\n");
}

//前序遍历递归方法打印结点内容
void PrintTree(TreeNode *pRoot)
{
    PrintTreeNode(pRoot);

if(pRoot != NULL)
    {
        if(pRoot->left != NULL)
            PrintTree(pRoot->left);

if(pRoot->right != NULL)
            PrintTree(pRoot->right);
    }
}

void DestroyTree(TreeNode *pRoot)
{
    if(pRoot != NULL)
    {
        TreeNode *pLeft = pRoot->left;
        TreeNode *pRight = pRoot->right;

delete pRoot;
        pRoot = NULL;

DestroyTree(pLeft);
        DestroyTree(pRight);
    }
}

 
 
 

												

【二叉查找树】04根据升序数组构造二叉查找树【Convert Sorted Array to Binary Search Tree】的更多相关文章

  1. [LeetCode] 108. Convert Sorted Array to Binary Search Tree ☆(升序数组转换成一个平衡二叉树)

    108. Convert Sorted Array to Binary Search Tree 描述 Given an array where elements are sorted in ascen ...

  2. LeetCode 108. 将有序数组转换为二叉搜索树(Convert Sorted Array to Binary Search Tree) 14

    108. 将有序数组转换为二叉搜索树 108. Convert Sorted Array to Binary Search Tree 题目描述 将一个按照升序排列的有序数组,转换为一棵高度平衡二叉搜索 ...

  3. 108. Convert Sorted Array to Binary Search Tree 109. Convert Sorted List to Binary Search Tree -- 将有序数组或有序链表转成平衡二叉排序树

    108. Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in ascendin ...

  4. LeetCode 108. Convert Sorted Array to Binary Search Tree (将有序数组转换成BST)

    108. Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in ascendin ...

  5. Convert Sorted Array to Binary Search Tree

    Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in ascending ord ...

  6. LeetCode:Convert Sorted Array to Binary Search Tree,Convert Sorted List to Binary Search Tree

    LeetCode:Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in asce ...

  7. Convert Sorted List to Binary Search Tree&&Convert Sorted Array to Binary Search Tree——暴力解法

    Convert Sorted List to Binary Search Tree Given a singly linked list where elements are sorted in as ...

  8. LeetCode108——Convert Sorted Array to Binary Search Tree

    题目: Given an array where elements are sorted in ascending order, convert it to a height balanced BST ...

  9. 37. leetcode 108. Convert Sorted Array to Binary Search Tree

    108. Convert Sorted Array to Binary Search Tree 思路:利用一个有序数组构建一个平衡二叉排序树.直接递归构建,取中间的元素为根节点,然后分别构建左子树和右 ...

  10. LeetCode: Convert Sorted Array to Binary Search Tree 解题报告

    Convert Sorted Array to Binary Search Tree Given an array where elements are sorted in ascending ord ...

随机推荐

  1. 【Atheros】Ath9k速率调整算法源码走读

    上一篇文章介绍了驱动中minstrel_ht速率调整算法,atheros中提供了可选的的两种速率调整算法,分别是ath9k和minstrel,这两个算法分别位于: drivers\net\wirele ...

  2. 一个Lumen多层拆分手记

    这个项目除了最基本的MVC,routes和之前讲过的ServiceProvider(服务商)依赖注入,还有Action (动作) .Repositories(仓储)等... 先讲一下仓储吧, 一般JA ...

  3. SpringBoot启动流程分析(六):IoC容器依赖注入

    SpringBoot系列文章简介 SpringBoot源码阅读辅助篇: Spring IoC容器与应用上下文的设计与实现 SpringBoot启动流程源码分析: SpringBoot启动流程分析(一) ...

  4. EasyDSS+EasyNVR实现幼儿园直播/工地直播等分权限观看直播视频的功能

    在EasyNVR互联网直播服务器使用说明书中有关于EasyNVR分组的介绍: "EasyNVR的功能定位就是为视频应用层输出视频设备接入/标准视频输出的能力平台层,只做基础的视频通道接入.视 ...

  5. 九度OJ 1186:打印日期 (日期计算)

    时间限制:1 秒 内存限制:32 兆 特殊判题:否 提交:6366 解决:2214 题目描述: 给出年分m和一年中的第n天,算出第n天是几月几号. 输入: 输入包括两个整数y(1<=y<= ...

  6. MySQL合并多行

    select id,group_concat(re_id order by re_id separator ",") as re_idfrom tablenamegroup by ...

  7. Android笔记之使用ZXing扫描二维码

    ZXing发布版下载地址:https://github.com/zxing/zxing/releases 为了能让官方Demo跑起来,先把ZXing核心部分core复制到自己的工程里 还要把andro ...

  8. 我的Android进阶之旅------>android:drawableLeft的用法

    有时候想在EditText左边放一个图片,如图所示: 就可以在xml布局文件中的EditText定义代码中,添加入下面的代码,即可实现: android:drawableLeft="@dra ...

  9. Java & 混型

    1.C++ & 混型 C++能够记住其模板参数的类型,对于混型来说,使用参数化类型更加优雅. #include <string> #include <ctime> #i ...

  10. 如何从统计中批量获取BD搜索关键词及对应的入口页面?

    前面我们介绍了通过cnzz的访问明细获取到搜索关键词及对应的入口页面,但是从BD搜索进来的关键词无法完整显示,只能呈现一些bd图片搜索的关键词,这是因为百度宣布从去年5月开始逐渐取消了referer关 ...