#include<stdio.h>
#include<stdlib.h>
typedef struct node
{
    int data;
    struct node *left, *right;
}Node;
typedef struct  node
{
    int data;
    Node *arr[20];
}Node 1;
Node1 *q;
int front=0, rear=-1;
void enQueue(Node *root)
{
    q->arr[++rear]=root;
}
Node* deQueue()
{
    return q->arr[front++];
}
Node *create(int num)
{
    Node *newNode=(Node*)malloc(1*sizeof(Node));
    newNode->data=num;
    newNode->left=NULL;
    newNode->right=NULL;
    return newNode;
}
Node *insert(Node *root, int num)
{
    if(root==NULL)
    return create(num);
    if(num<root->data)
    root->left=insert(root->left,num);
    if(num>root->data)
    root->right=insert(root->right,num);
    return root;
}
void levelorder()
{
    
}
int main()
{
    int, n,i,num;
    scanf("%d",&n);
    if(n<0)
    {
        printf("invalid input");
        return 0;
    }
    for(i=0;i<n;i++)
    {
        scanf("%d",&num);
        root=insert(root,num);
    }
    levelorder(root);
    return 0;
}