// editor3
// editor2
// editor1
#include<stdio.h>
#include<stdlib.h>
typedef struct treenode{
    int data;
    struct treenode *right;
    struct treenode *left;
}node;
node *root =NULL;
node *create(int num){
    node *newnode = (node*)malloc(sizeof(node));
    newnode->data=num;
    newnode->left=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);
    else
    root->right = insert(root->right,num);
    return root;
}
void level(node *root){
    if(root == NULL){
        return;
    }
    node queue[100];
    int front = 0,rear = 0;
    queue[rear++]=root;
    while(front<rear){
        node *curr = queue[front++];
        printf("%d",*curr->data)
        if(*curr->left){
            queue[rear++]=curr->left;
        }
    }
}
int main(){
    int num,size;
    scanf("%d",&size);
    if(size<0){
        printf("Invalid input");
        return 0;
}
for(int i = 0;i<size;i++){
scanf("%d",&num);
root =insert(root,num);
}
///insert(root);
levelorder(root);
return 0;
}