// editor4
#include<stdio.h>
#include<stdlib.h>
typedef struct node{
    int data;
    struct node *left,*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);
    if(num<root->data)
      root->left=insert(root->left,num);
     else if(num>root->data)
      root->right=insert(root->right,num);
      return root;
}
void postorder(node *root)
{
    if(root!=NULL)
    {
        postorder(left->root);
        postorder(right->root);
        printf("%d",root->data);
    }
}

int main()
{
    int size,num;
    scanf("%d",&size);
    for(i=0;i<size;i++)
    {
        scanf("%d",&num);
        root=insert(root,num);
    }
    postorder(root);
    return 0;
}