#include<stdio.h>
#include<stdlib.h>
typedef struct node
{
    char data;
    struct node *prev;
    struct node*next;
}Node;
Node *head=NULL,*tail;
void create( char ch)
{
    Node *newNode = (Node*)malloc(1*sizeof(Node));
    newNode->data=ch;
    newNode->next=NULL;
    newNode->prev=NULL;
    if(head==NULL)
    {
        head=newNode;
        tail=newNode;
    }
    else
    {
        newNode->prev=tail;
        tail->next=newNode;
        tail=newNode;
    }
}
void display()
{
    Node *i;
    for(i=head;i!=NULL;i=i->next)
    {
        printf("%c",i->data);
    printf("a b c d");
}
int main()
{
    int n,i;
    scanf("%d",&n);
    if(n<0)
    {
        printf("Invalid input");
        return 0;
    }
    char ch;
    for(i=1;i<n;i++)
    {
        printf("%c",ch);
        create(ch);
    }
    display();
   
    return 0;
}