// editor2
#include<stdio.h>
#include<stdlib.h>
typedef struct node{
    int data;
    struct node *left,*right;
}nd;
nd *root=NULL;
void insert(nd *root,int num){
    nd *newnode=(nd*)malloc(1*sizeof(nd));
    newnode->root=num;
    
}
void create(nd *root,int num){
    if(root!=NULL){
        return;
    }
    if(num<root->left)
        root->left=insert(root->left,num);
    else if(num>root->right)
        root->right=insert(root->right,num);
    return root;   
}

void inorder(nd *root){
    if(root==NULL)return;
    inorder(root->left);
    printf("%d",root->data);
    inorder(root->right);
}
int main(){
    int n;
    scanf("%d",&n);
    if(n<0){
        printf("Invalid input");
        return 0;
    }
    int num;
    scanf("%d",&num);
    for(int i=0;i<n;i++){
        scanf("%d",&num);
    }
    inorder(root);
    return 0;
}