#N=int(input())
N=10000
import random
alpha="abcdefghijklmnopqrstuvwxyz"
list=list(alpha)
ki_list=[]
start="a"
i=1
con=0
while i<=N:
    word=random.sample(list,10)
    word.insert(0,start)
    start=word[-1]
    if start=="n":
        word.append("a")
        start="a"
    if i==N:
        word.append("n")
    word="".join(word)
    for j in ki_list:
        if j==word:
            con=1
    if con==1:
        continue
    ki_list.append(word)

    print(word)
    con=0
    i+=1