n=int(eval(input()))

alpha=[chr(i) for i in range(97, 97+26)]

def calc(x):

  if x//26>0:

    return calc(x//26-1) + str(x%26).zfill(2)

  return str(x%26).zfill(2)

wk=calc(n-1)

ans=""

for i in range(0,len(wk),2):

  ans+=alpha[int(wk[i:i+2])]

print(ans)
n=int(eval(input()))

alpha=[chr(i) for i in range(97,97+26)]

def test(x,t):

  if x//t>0:

    return test(x//t-1,t)+alpha[x%t]

  return alpha[x%t]

print((test(n-1,26)))
n = int(eval(input()))
alpha = [chr(i) for i in range(97, 97 + 26)]


def calc(x):
    if x // 26 > 0:
        return calc(x // 26 - 1) + str(x % 26).zfill(2)
    return str(x % 26).zfill(2)


wk = calc(n - 1)
ans = ""
for i in range(0, len(wk), 2):
    ans += alpha[int(wk[i : i + 2])]
print(ans)

n = int(eval(input()))
alpha = [chr(i) for i in range(97, 97 + 26)]


def test(x, t):
    if x // t > 0:
        return test(x // t - 1, t) + alpha[x % t]
    return alpha[x % t]


print((test(n - 1, 26)))

-def calc(x): -    if x // 26 > 0: -        return calc(x // 26 - 1) + str(x % 26).zfill(2) -    return str(x % 26).zfill(2) +def test(x, t): +    if x // t > 0: +        return test(x // t - 1, t) + alpha[x % t] +    return alpha[x % t] -wk = calc(n - 1) -ans = "" -for i in range(0, len(wk), 2): -    ans += alpha[int(wk[i : i + 2])] -print(ans) +print((test(n - 1, 26)))