// editor1
#include<stdio.h>
#include<stdlib.h>
typedef struct node{
    int data;
    struct node *next;
    struct node *prev;
}Node;
Node *head,*tail;
void create(int num){
    Node *newnode = (Node*) malloc (1*sizeof(Node));
    newnode->data = num;
    newnode->next = NULL;
    newnode->prev = NULL;
    if(head == NULL){
        head = newnode;
        tail = newnode;
    }else{
        tail->next = newnode;
        newnode->prev = tail;
        tail = newnode;
    }
}
void deletion(){
     if(head==NULL){
         printf("Head is null");
     }else{
         tail->previous->next = NULL;
     }
}
void display(){
    Node *itr;
    for(itr=head;itr!=NULL;itr=itr->next){
        printf("%d ",itr->data);
    }
}

int main(){
    int n,num,itr;
    scanf("%d",&n);
    if(n<0){
        printf("Invalid input");
    }
    for(itr=0;itr<n;itr++){
        scanf("%d",&num);
        create(num);
    }
    display();
    deletion();
    display();
    return 0;
}