#include <stdio.h>
#include <sdtlib.h>

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

Node *head=NULL, *tail=NULL;

void create(int num){
    Node *node=(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(){
    struct node *itr;
    for(itr=head; itr!=NULL; itr=itr->next){
        printf("%d", ptr->data);
    }
}


int main(){
    int n, num;
    scanf("%d", &n);
    if(n<0){
        printf("Invalid input");
    }
    
    for(int i=0;i<n; i++){
        scanf("%d", &num);
        if(num<0){
            printf("Invalid input");
        }
        create(num);
    }
    display();
    return 0;
}