// editor5
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
struct Node 
{
    int data;
    struct Node *next;
};
struct Node* createNode(int data) 
{
    struct Node* newNode = (struct Node*) malloc(sizeof(struct Node));
    newNode->data = data;
    newNode->next = NULL;
    return newNode;
}
void printList(struct Node* head) 
{
    struct Node* temp = head;
    while (temp != NULL) 
    {
        printf("%d", temp->data);
        temp = temp->next;
        if (temp != NULL) printf(" ");
    }
}
void insertMiddle(struct Node **head, int val, int n) 
{
    struct Node* newNode = createNode(val);
    if (*head == NULL) 
    {
        *head = newNode;
        return;
    }
    int mid = n / 2; 
    struct Node *temp = *head;
    for (int i = 0; i < mid - 1; i++) 
    {
        temp = temp->next;
    }
    if (n == 0) 
    { 
        *head = newNode;
        return;
    }
    else if (mid == 0) 
    {
        newNode->next = *head;
        *head = newNode;
        return;
    }
    newNode->next = temp->next;
    temp->next = newNode;  
}
int main() 
{
    int n, val;
    if (scanf("%d", &n) != 1 || n < 0 || n > 1000) 
    {
        printf("Invalid input");
        return 0;
    }
    struct Node* head = NULL;
    struct Node* tail = NULL;
    for (int i = 0; i < n; i++) 
    {
        int x;
        if (scanf("%d", &x) != 1) 
        {
            printf("Invalid input");
            return 0;
        }
        struct Node* newNode = createNode(x);
        if (head == N