1 #include<stdio.h>
2 #include<stdlib.h>
3 typedef struct node *btlink;
4 struct node
5 {
6 int data;
7 btlink left;
8 btlink right;
9 int t;
10 };
11
12 btlink BT;
13 void insert(btlink q, int x)
14 {
15 btlink p = (btlink)malloc(sizeof(node));
16 p->data = x;
17 p->left = NULL;
18 p->right = NULL;
19 p->t=0;
20 if(q == NULL)
21 {
22 BT = p;
23 //printf("BT=%d\n",BT->t);
24 return ;
25 }
26 while(q->left!=p&&q->right!=p)
27 {
28 if(x<q->data)
29 {
30 if(q->left)
31 {
32 q->t++;
33 q = q->left;
34 }
35 else
36 {
37 q->t++;
38 q->left = p;
39 }
40 }
41 else
42 {
43 if(q->right)
44 {
45 q = q->right;
46 }
47 else
48 {
49 q->right = p;
50 }
51 }
52 }
53 return;
54 }
55 void InOrder(btlink root,int k)
56 {
57
58 while(k!=root->t+1)
59 {
60 //printf("k=%d t=%d\n",k,root->t);
61 if(k>root->t+1)
62 {
63 k=k-root->t-1;
64 root=root->right;
65 }
66 else
67 {
68
69 root=root->left;
70 }
71 }
72 printf("%d\n",root->data);
73 }
74
75 int main()
76 {
77 int n,i,index=0,x;
78 char a[8];
79 scanf("%d",&n);
80 BT=(btlink)malloc(sizeof(node));
81 BT=NULL;
82 for(i=0;i<n;i++)
83 {
84 scanf("%s",a);
85 if(a[0]=='a')
86 {
87 scanf("%d",&x);
88 insert(BT,x);
89 }
90 else if(a[0]=='p')
91 {
92
93 index++;
94 InOrder(BT,index);
95 }
96 }
97 return 0;
98 }
