// editor1
#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);
    }
    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 postorder(node *root)
{
    if(root!=NULL)
    {
        postorder(root->left);
           printf("%d ",root->data);
        postorder(root->right);
     
    }
}
int main()
{
    int size,num;
    scanf("%d",&size);
    if(size<=0)
    {
        printf("Invalid input");
        return 0;
    }
    for(int i=0;i<size;i++)
    {
    scanf("%d",&num)
    if(num<0)
    {
        printf("Invalid input");
    }
    
    root=insert(root,num);
    
}
postorder(root);
return 0;
}