algorithm/source/FindNextTreeNode.cpp at main · butcher-x/algorithm · GitHub

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
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
#include<iostream>
#include<queue>
#include<list>
using namespace std;
struct Node
{
    int data;
    Node* parent;
    Node* left;
    Node* right;
    Node(int _data):data(_data), parent(nullptr), left(nullptr), right(nullptr){}
};

void del(Node* nd)
{
    if(nd == nullptr)
        return;
    del(nd->left);
    del(nd->right);
    delete nd;
}

Node* genTree_in(int maxLayers, int maxVar, int curLayer, Node* parent)
{
    curLayer++;
    if(curLayer > maxLayers)
        return nullptr;
    int ran;
    if(curLayer <= 2)
        ran = rand() % 4;
    else
        ran = rand() % 2;
    if(ran == 0 && curLayer != 1)
        return nullptr;
    else
    {
        Node* nd = new Node(rand() % maxVar + 1);
        nd->parent = parent;
        nd->left = genTree_in(maxLayers, maxVar, curLayer, nd);
        nd->right = genTree_in(maxLayers, maxVar, curLayer, nd);
        return nd;
    }
}
Node* generateRandomTree(int maxLayers, int maxVar)
{
    if(maxLayers <= 0)
        return nullptr;
    srand(time(nullptr));
    Node* root = genTree_in(maxLayers, maxVar, 0, nullptr);
    return root;
}


Node* findNextPre(Node* nd)
{
    if(nd == nullptr)
        return nullptr;
    if(nd->left != nullptr)
        return nd->left;
    if(nd->right != nullptr)
        return nd->right;
    Node* pa = nd->parent;
    while(pa != nullptr)
    {
        if(pa->right != nd)
            return pa->right;
        nd = pa;
        pa = pa->parent;
    }
    return nullptr;
}

Node* findNextPost_in(Node* nd)
{
    if(nd->left == nullptr && nd->right == nullptr)
        return nd;
    if(nd->left != nullptr)
        return findNextPost_in(nd->left);
    if(nd->right != nullptr)
        return findNextPost_in(nd->right);
}
Node* findNextPost(Node* nd)
{
    if(nd == nullptr || nd->parent == nullptr)
        return nullptr;
    Node* parent = nd->parent;
    if(parent->right == nd || parent->right == nullptr)
        return parent;
    return findNextPost_in(parent->right);
}

Node* findNextIn_in(Node* nd)
{
    if(nd->left == nullptr)
        return nd;
    else
        return findNextIn_in(nd->left);
}

Node* findNextIn(Node* nd)
{
    if(nd == nullptr)
        return nullptr;
    if(nd->right != nullptr)
        return findNextIn_in(nd->right);
    Node* parent = nd->parent;
    while(parent != nullptr)
    {
        if(parent->right == nd)
        {
            nd = parent;
            parent = parent->parent;
        }
        return parent;
    }
    return nullptr;
}


Node* randomNode(Node* root)
{
    if(root == nullptr)
        return nullptr;
    srand(time(nullptr));
    Node* tmp = root;
    queue<Node*>que;
    que.push(tmp);
    while(!que.empty())
    {
        tmp = que.front();
        que.pop();
        if(rand() % 2 == 0)
            return tmp;
        if(tmp->left != nullptr)
            que.push(tmp->left);
        if(tmp->right != nullptr)
            que.push(tmp->right);
    }
    return root;
}

void pre(list<Node*> &orderList, Node* nd)
{
    if(nd == nullptr)
        return;
    orderList.push_back(nd);
    pre(orderList, nd->left);
    pre(orderList, nd->right);
}
void in(list<Node*> &orderList, Node* nd)
{
    if(nd == nullptr)
        return;
    in(orderList, nd->left);
    orderList.push_back(nd);
    in(orderList, nd->right);
}

void post(list<Node*> &orderList, Node* nd)
{
    if(nd == nullptr)
        return;
    post(orderList, nd->left);
    post(orderList, nd->right);
    orderList.push_back(nd);
}

void tester(int times, Node* (*func)(Node*))
{
    void (*trav)(list<Node*>&, Node*);
    if(func == findNextPre)
        trav = pre;
    else if(func == findNextIn)
        trav = in;
    else
        trav = post;
    for(int i = 0; i < times; i++)
    {
        Node* root = generateRandomTree(20, 10000);
        Node* nd = randomNode(root);
        list<Node*> orderList;
        trav(orderList, root);
        Node* next = func(nd);
        auto p = orderList.begin();
        while((*p) != nd)
            p++;
        p++;
        if((*p) == next || (p == orderList.end() && next == nullptr))
        {
            cout << "success" << endl;
            del(root);
            continue;
        }
        cout << "wrong..." << endl;
        cout << "traverse result: " << endl;
        for(auto i : orderList)
            cout << i->data << endl;
        return;
    }
}

int main()
{
    tester(1000000, findNextIn);
}