n = int(eval(input()))

ans = ''

while n > 0:

    n -= 1

    ans += chr(ord('a') + n % 26)

    n //= 26

print((ans[::-1]))
n = int(eval(input()))

ans = ''

while n:

    n -= 1

    ans += chr(ord('a') + n % 26)

    n //= 26

print((ans[::-1]))
n = int(eval(input()))
ans = ""
while n > 0:
    n -= 1
    ans += chr(ord("a") + n % 26)
    n //= 26
print((ans[::-1]))

n = int(eval(input()))
ans = ""
while n:
    n -= 1
    ans += chr(ord("a") + n % 26)
    n //= 26
print((ans[::-1]))

-while n > 0: +while n: