1 #include<cstdio>
2 #include<algorithm>
3 using namespace std;
4 struct node{
5 node *left;
6 node *right;
7 int height;
8 int data;
9 node(int x):data(x),left(NULL),right(NULL),height(0){}
10 };
11 struct avl
12 {
13 node* root;
14 int Height(node *NODE) {
15 if(NODE==NULL) return -1;
16 return NODE->height;
17 }
18 node* RightRotate(node *a) {
19 node *b = a->left;
20 a->left = b->right;
21 b->right = a;
22 a->height = max(Height(a->left), Height(a->right));
23 b->height = max(Height(b->left), Height(b->right));
24 return b;
25 }
26 node* LeftRotate(node *a) {
27 node *b = a->right;
28 a->right = b->left;
29 b->left = a;
30 a->height = max(Height(a->left), Height(a->right));
31 b->height = max(Height(b->left), Height(b->right));
32 return b;
33 }
34 node* LeftRightRotate(node *a) {
35 a->left = LeftRotate(a->left);
36 return RightRotate(a);
37 }
38 node* RightLeftRotate(node* a) {
39 a->right = RightRotate(a->right);
40 return LeftRotate(a);
41 }
42 node* Insert(int x, node* t) {
43 if(t == NULL) {
44 t = new node(x);
45 return t;
46 } else if(x < t->data) {
47 t->left = Insert(x,t->left);
48 if(Height(t->left) - Height(t->right) == 2) {
49 if(x < t->left->data) {
50 t = RightRotate(t);
51 } else {
52 t = LeftRightRotate(t);
53 }
54 }
55 } else {
56 t->right = Insert(x,t->right);
57 if(Height(t->right) - Height(t->left) == 2) {
58 if(x > t->right->data) {
59 t = LeftRotate(t);
60 } else {
61 t = RightLeftRotate(t);
62 }
63 }
64 }
65 t->height = max(Height(t->left), Height(t->right)) + 1;
66 return t;
67 }
68 /*node* Delete(int x,node *t) {
69 if(t==NULL) return NULL;
70 if(t->data == x) {
71 if(t->right == NULL) {
72 node* temp = t;
73 t = t->left;
74 free(temp);
75 } else {
76 node* head = t->right;
77 while(head->left) {
78 head=head->left;
79 }
80 t->data = head->data; //just copy data
81 t->right = Delete(t->data, t->right);
82 t->height = max(Height(t->left), Height(t->right)) + 1;
83 }
84 return t;
85 else if(t->data < x) {
86 Delete(x, t->right);
87 if(t->right) Rotate(x, t->right);
88 } else {
89 Delete(x, t->left);
90 if(t->left) Rotate(x, t->left);
91 }
92 if(t) Rotate(x, t);
93 }
94 }*/
95 };
96 avl a;
97 int main()
98 {
99 int n,x;
100 scanf("%d",&n);
101 a.root=NULL;
102 for(int i=0;i<n;i++)
103 {
104 scanf("%d",&x);
105 a.root=a.Insert(x,a.root);
106 }
107 return 0;
108 }
