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

typedef struct Node{
int data;
struct Node *next;
}Node;
 
 int main(){
 int n,x;
 if(scanf("%d",&n) !=1||n<=0){
 printf("Invalid input\n");
 return 0;
 }
 Node *head=NULL,*tail=NULL,*p;
 for(int i=0;i<n;i++);
 if(scanf("%d",&x) !=1){
 printf("Invalid input\n");
 return 0;
 }
 p=malloc(sizeof(Node));
 p->data=x;p->next=NULL;
 if(!head)head=tail=p;
 else(tail->next=p;tail=p;)
 }
 for(p=head;p;p=p->next)printf("%d",p->data);
 printf("\n");
 return 0;
 }