N = int(eval(input()))



ans = []

lst = []

n = N



while n > 26:

    x = n%26

    if x == 0:

        n = n//26 - 1

    else:

        n = n//26

    lst.append(x)





for i in range(len(lst)):

    x = lst[i]

    if x == 0:

        y = chr(97+25)

    else:

        y = chr(97 + x-1)

    ans.append(y)



ans.append(chr(97 + n-1))



ans = ans[::-1]



ans = ''.join(ans)

print(ans)

n = int(eval(input()))

ans = ""

while n:

    n -= 1

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

    n //= 26



print((ans[::-1]))
N = int(eval(input()))
ans = []
lst = []
n = N
while n > 26:
    x = n % 26
    if x == 0:
        n = n // 26 - 1
    else:
        n = n // 26
    lst.append(x)
for i in range(len(lst)):
    x = lst[i]
    if x == 0:
        y = chr(97 + 25)
    else:
        y = chr(97 + x - 1)
    ans.append(y)
ans.append(chr(97 + n - 1))
ans = ans[::-1]
ans = "".join(ans)
print(ans)

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

-N = int(eval(input())) -ans = [] -lst = [] -n = N -while n > 26: -    x = n % 26 -    if x == 0: -        n = n // 26 - 1 -    else: -        n = n // 26 -    lst.append(x) -for i in range(len(lst)): -    x = lst[i] -    if x == 0: -        y = chr(97 + 25) -    else: -        y = chr(97 + x - 1) -    ans.append(y) -ans.append(chr(97 + n - 1)) -ans = ans[::-1] -ans = "".join(ans) -print(ans) +n = int(eval(input())) +ans = "" +while n: +    n -= 1 +    ans += chr(n % 26 + ord("a")) +    n //= 26 +print((ans[::-1]))