// editor5// editor2
// editor1
#include<stdio.h>
#include<stdlib.h>
typedef struct Node{
    int data;
    struct Node *left;
    struct Node *right;
}nd;
nd *root=NULL;
nd *create(int num){
    nd *newnode=(nd*)malloc(sizeof(nd));
    newnode->data=num;
    newnode->left=newnode->right=NULL;
    return newnode;
}
nd *insert(nd *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 inorder(nd *root){
    if(root==NULL)return;
    
        inorder(root->left);
         printf("%d",root->data);
        inorder(root->right);
       
}
int main(){
    int n,num;
    nd *root=NULL;
    scanf("%d",&n);
    if(n<0){
        printf("Invalid input");
        return 0;
    }
    for(int i=0;i<n;i++){
       scanf("%d",&num);
       root=insert(root,num);
    }
    postorder(root);
    return 0;
}