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