n = int(eval(input()))

eigo = 'abcdefghijklmnopqrstuvwxyz'



keta = 1

j = 1

while n > 26**j:

    n -= 26**j

    keta += 1

    j += 1



n = n-1

ans =''



while keta != 0:

    a = n //(26**(keta-1))

    if a != 0:

        n = n -(26**(keta-1)*a)

        ans += eigo[a]

    else:

        ans+= eigo[0]

    keta -= 1



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

eigo = 'abcdefghijklmnopqrstuvwxyz'



keta = 1

while n > 26**keta:

    n -= 26**keta

    keta += 1



ans =''

n = n-1

for i in range(keta):

    a =n // 26**(keta-1-i)

    ans += eigo[a]

    n = n % (26**(keta-1-i))

print(ans)

n = int(eval(input()))
eigo = "abcdefghijklmnopqrstuvwxyz"
keta = 1
j = 1
while n > 26**j:
    n -= 26**j
    keta += 1
    j += 1
n = n - 1
ans = ""
while keta != 0:
    a = n // (26 ** (keta - 1))
    if a != 0:
        n = n - (26 ** (keta - 1) * a)
        ans += eigo[a]
    else:
        ans += eigo[0]
    keta -= 1
print(ans)

n = int(eval(input()))
eigo = "abcdefghijklmnopqrstuvwxyz"
keta = 1
while n > 26**keta:
    n -= 26**keta
    keta += 1
ans = ""
n = n - 1
for i in range(keta):
    a = n // 26 ** (keta - 1 - i)
    ans += eigo[a]
    n = n % (26 ** (keta - 1 - i))
print(ans)

-j = 1 -while n > 26**j: -    n -= 26**j +while n > 26**keta: +    n -= 26**keta -    j += 1 +ans = "" -ans = "" -while keta != 0: -    a = n // (26 ** (keta - 1)) -    if a != 0: -        n = n - (26 ** (keta - 1) * a) -        ans += eigo[a] -    else: -        ans += eigo[0] -    keta -= 1 +for i in range(keta): +    a = n // 26 ** (keta - 1 - i) +    ans += eigo[a] +    n = n % (26 ** (keta - 1 - i))