#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(1*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*preorder(Node*root)
{
    if(root!=NULL)
    {
        printf("%d ",root->data);
        preorder(root->left);
        preorder(root->right);
    }
}
void* inorder(Node *root)
{
    if(root!=NULL)
    {
        inorder(root->left);
        printf("%d ",root->data);
        inorder(root->right);
        
    }
}
printf("\n");
void* postorder(Node *root)
{
    if(root!=NULL)
    {
        postorder(root->left);
        postorder(root->right);
        printf("%d ",root->data);
        
        
    }
}
int main()
{
    int   size,i,num;
    scanf("%d",&size);
    for(i=1;i<=size;i++)
    {
        scanf("%d",&num);
        root=insert(root,num);
    }
    preorder(root);
    inorder(root);
    postorder(root);
}