#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;
    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=itr->next)
}
int main() {
    int size,itr,num;
    scanf("%d",&size);
    if(size<0){
        printf("Invalid input");
        return 0;
    }
}
}