#include<stdio.h>
#include<stdio.h>
typedef struct node{
    int data;
    struct node *next;
}Node;
Node *head=NULL,*tail=NULL;
void create (int num){
    Node *newnode=(Node*)malloc(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->next){
        printf("%d",itr->data);
    }
}
    int main()
    {
        int size,num,itr;
        scanf("%d",&size);
        for(size<=0){
            printf("Invalid input");
            return 0;
        }
        for(int itr=1;itr<=size;itr++){
            if(scanf("%d",&num)!=1){
                printf("Invalid input");
                return 0;
            }
            if(num< -1000||num>1000){
                printf("Invalid input");
                return 0;
            }
            create (num);
        }
        display();
        return 0;
    }