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()))

n = N

ans = ''

while n > 0:

  n -= 1

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

  n //= 26

print(ans)
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()))
n = N
ans = ""
while n > 0:
    n -= 1
    ans = chr(ord("a") + n % 26) + ans
    n //= 26
print(ans)

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