#include<stdio.h>
#include<stdlib.h>
typedef struct node{
    int data;
    struct node *next;
}Node;
Node*head=0,*tail;
void create(int num){
    Node *newnode=(Node*)malloc(sizeof(Node));
    newnode->data=num;
    newnode->next=NULL;
    if(head==NULL){
        head=newnode;
        tail=newnode;
    }
    else{
        tail->next=newnode;
        tail=newnode;
    }
}
int display(){
    Node *i;
    for(i=head;i!=NULL;i->next){
        if(i->data%2==0){
            printf("%d",i->data);
            i=1;
        }
    }
    if(j==0){
        printf("empty";
        return 0;)
    }
    
}
int main(){
    int size,num;
    scanf("%d",&size);
    if(size<0){
        printf("Invalid input");
        return 0;
    }
    for(int i=0;i<size;i++){
        if(!(scanf("%d",&num))){
            printf("Inavlid input");
            return 0;
        }
    }
}