// yukicoder: No.701 ひとりしりとり
// 2019.5.2 bal4u

#include <stdio.h>

#if 1
#define pc(c) putchar_unlocked(c)
#else
#define pc(c) putchar(c)
#endif

void outs(char *s) { while (*s) pc(*s++); }

char a[10] = "aaaaaa\n";

int main()
{
	int i, n;
	
	scanf("%d", &n);
	while (--n) {
		for (i = 1; i <= 4; i++) {
			if (a[i] < 'z') { a[i]++; break; }
			else a[i] = 'a';
		}
		outs(a);
	}
	outs("an\n");
	return 0;
}