advanced-data-structures/BST_left_insertion_of_equal_elements.cpp at master · pushpendrapratap/advanced-data-structures · 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
//In this BST, equal elements will go in left-subtree

#include<iostream>
#include<stdlib.h>
using namespace std;

typedef struct tree{
	struct tree* left;
	struct tree* right;
	struct tree* parent;
	int info;
}node;

node* create(node* &root,int x){    //Used for both creation and insertion of BST
	node* z=new node;
	z->info=x;
	z->left=z->right=z->parent=NULL;

	node* current=new node;
	current=root;
	node* hero=new node;
	hero=NULL;

	while(current!=NULL){
		  hero=current;
			if(z->info<=current->info)
			   current=current->left;
			else
			   current=current->right;
	}
	if(hero==NULL)
		   root=z;
	else if(z->info <= hero->info){
		 hero->left=z;
		 z->parent=hero;
	}
	else{
	    hero->right=z;
		z->parent=hero;
	}
	return root;
}

/*void transplant(node* &root , node* &u , node* &v){     //Pushpendra's version of transplant()
	if(u->parent==NULL){
		root=v;
	}
	else if(u==u->parent->left && v!=NULL){
	    u->parent->left=v;
	    v->parent=u->parent;
	  }
	else if(u==u->parent->left && v==NULL)
	    u->parent->left=v;
	else if(u==u->parent->right && v!=NULL){
	    u->parent->right=v;
	    v->parent=u->parent;
      }
	else if(u==u->parent->right && v==NULL)
	    u->parent->right=v;
}*/
void transplant(node* &root , node* &u , node* &v){       //Cormen's version of transplant()
	if(u->parent==NULL)
		root=v;
	else if(u==u->parent->left)
	    u->parent->left=v;
	else if(u==u->parent->right)
	    u->parent->right=v;
	if(v!=NULL)
	    v->parent=u->parent;
}

node* find_max(node* &root){
   node* temp=root;
   	if(temp->right==NULL)
   		return temp;
	else
		return find_max(temp->right);
}

node* search(node* &root,int x){
	node* temp=root;
	while(temp!=NULL){
		if(temp->info == x)
			return temp;
		else if(x < temp->info)
			temp=temp->left;
		else if(x > temp->info)
			temp=temp->right;
	}
	cout<<"\nelement is not in Tree \n";
}
/*node* search(node* root,int x){              //Recursive search
	node* temp=root;
	if(x < temp->info)
	   return search(temp->left,x);
	else if(x==temp->info)
	   return temp;
	else if(x > temp->info)
	   return search(temp->right,x);
}*/

void del(node* &root,node* &p){
	if(p->left==NULL && p->right!=NULL)
	   transplant(root,p,p->right);
	else if(p->right==NULL && p->left!=NULL)
	    transplant(root,p,p->left);
	else{
		node* y=find_max(p->left);
		if(y->parent!=p){
		   transplant(root,y,y->left);
		   y->left=p->left;
		   y->left->parent=y;

		   transplant(root,p,y);
		   y->right=p->right;
		   y->right->parent=y;
		}
		else{
		   transplant(root,p,y);
		   y->right=p->right;
		   y->right->parent=root;
		}
	}
}

void inorder(node* &p){
   if(p!=NULL){
      inorder(p->left);
	  cout<<p->info<<" ";
	  inorder(p->right);
   }
}

int main(){
	node* root=new node;
	root=NULL;

    for(int i=1;i<=10;i++)
        root=create(root,i*i*i-7*i*i-i+7);
//    root=create(root,i);
    node* temp=search(root,0);
//	node* temp=search(root,1);

    del(root,temp);   temp=search(root,0); del(root,temp);
	inorder(root);
	cout<<"\n"<<root->info;
}