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