N = int(eval(input()))

ans = ''

while N > 0:

    N -= 1

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

    N //= 26

ans = ans[::-1]

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

arr = []

while 0 < N:

    N -= 1

    arr.append(N % 26)

    N //= 26

ans = ''

for a in reversed(arr):

    ans += chr(ord('a')+a)

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

N = int(eval(input()))
arr = []
while 0 < N:
    N -= 1
    arr.append(N % 26)
    N //= 26
ans = ""
for a in reversed(arr):
    ans += chr(ord("a") + a)
print(ans)

+arr = [] +while 0 < N: +    N -= 1 +    arr.append(N % 26) +    N //= 26 -while N > 0: -    N -= 1 -    ans += chr(ord("a") + N % 26) -    N //= 26 -ans = ans[::-1] +for a in reversed(arr): +    ans += chr(ord("a") + a)