#include<iostream>
using namespace std;
int f;
typedef struct BiTNode
{
int data;
struct BiTNode *lchild,*rchild;
}BiTNode,*BiTree;
void visit(BiTree T)
{
if(T->data!=NULL)
{
if(f==1)
{
cout<<" "<<T->data;
}
else
{
cout<<T->data;
f=1;
}
}
}
void insert(BiTree &T,int key)
{
if(T==NULL)
{
T=new BiTNode;
T->lchild=T->rchild=NULL;
T->data=key;
return ;
}
if(key<T->data)
insert(T->lchild,key);
else
insert(T->rchild,key);
}
void InOrder(BiTree T)
{
if(T)
{
InOrder(T->lchild);
visit(T);
InOrder(T->rchild);
}
}
int main()
{
int m,i,n;
BiTree T;
while(cin>>m)
{
T=NULL;
for(i=0;i<m;i++)
{
cin>>n;
insert(T,n);
}
f=0;
InOrder(T);
cout<<"\n";
}
return 0;
}