1 /*
 2 4
 3 1 3 4 2
 4 
 5 1 3 2 4
 6 */
 7 #include<iostream>
 8 #include<stdio.h>
 9 #include<cstring>
10 #include<cstdlib>
11 using namespace std;
12 
13 struct node
14 {
15     int rp;
16     struct node *lchild;
17     struct node *rchild;
18 };
19 
20 int n,len;
21 
22 void mem(struct node *p)
23 {
24     p->rp=0;
25     p->lchild=NULL;
26     p->rchild=NULL;
27 }
28 void insert_ecs(struct node **p,int x)
29 {
30     if((*p)==NULL)
31     {
32         (*p)=(struct node*)malloc(sizeof(struct node));
33         mem(*p);
34         (*p)->rp=x;
35         return;
36     }
37     if( (*p)->rp > x)
38         insert_ecs( &(*p)->lchild,x);
39     else insert_ecs( &(*p)->rchild,x);
40 }
41 void serch(struct node *p)
42 {
43     printf("%d",p->rp);
44     len++;
45     if(len!=n) printf(" ",p->rp);
46     else printf("\n");
47 
48     if( p->lchild!=NULL )
49         serch(p->lchild);
50     if( p->rchild!=NULL )
51         serch(p->rchild);
52 }
53 void deal(struct node *p)
54 {
55     if(p->lchild!=NULL)
56         deal(p->lchild);
57     if(p->rchild!=NULL)
58         deal(p->rchild);
59     free(p);
60 }
61 int main()
62 {
63     int i,x;
64     while(scanf("%d",&n)>0)
65     {
66         struct node *root=NULL;
67         for(i=1;i<=n;i++)
68         {
69             scanf("%d",&x);
70             insert_ecs(&root,x);
71         }
72         len=0;
73         serch(root);
74         free(root);
75     }
76     return 0;
77 }