#include<stdio.h>
#include<stdlib.h>

typedef struct node {
    int data;
    struct node* next;
}Node;

Node *head,*tail;
void create(int num) {
    Node *newnode = (Node*) malloc (1 * sizeof(Node));
    newnode->data=num;
    newnode->next=NULL;
    if(head==NULL){
        head=newnode;
        tail=newnode;
    }
    else{
        tail->next=newnode;
        tail=newnode;
    }
}
void display() {
    Node *itr;
    for(itr=head;itr!=NULL;itr=itr->next)
   
    

int main()
{
    int num,size,itr;
    scanf("%d",&size);
    for(itr=1;itr<=size;itr++){
    if(!scanf("%d",&num)){
        printf("Invalid input");
        return 0;
    }
    else if(itr % 2== 0){
            printf("%d ",num);
    }
     
    create(num);
    
            
        }
         display(); 
        }