#include<stdio.h>
#include<stdlib.h>
int size;
typedef struct node{
    int data;
    struct node *left;
    struct node *right;
}Node;
Node *root=NULL;
Node *create(int num){
    Node *newNode =(Node*)malloc(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);
    }else if(num < root->data){
        root->left=insert(root->left,num);
    }else if(num > root->data){
        root->right=insert(root->right,num);
    }return root;
}

void display(Node *root){
    if(root == NULL){
        return root;
    }else if(root->left!=NULL){
        return display(root->left);
    }
    else if(root->right!=NULL){
        return display(root->right);
    }
    return root;
}
int main(){
    int i,num;
    scanf("%d",&size);
    if(size<0){
        printf("Invalid input");
        return 0;
    }
    for(i=0;i<size;i++){
        scanf("%d",&num);
        root=insert(root,num);
    }
    return 0;
}