Problem:
Score : 300 points

Problem Statement

1000000000000001 dogs suddenly appeared under the roof of Roger's house, all of which he decided to keep. The dogs had been numbered 1 through 1000000000000001, but he gave them new names, as follows:

the dogs numbered 1,2,\cdots,26 were respectively given the names a, b, ..., z;

the dogs numbered 27,28,29,\cdots,701,702 were respectively given the names aa, ab, ac, ..., zy, zz;

the dogs numbered 703,704,705,\cdots,18277,18278 were respectively given the names aaa, aab, aac, ..., zzy, zzz;

the dogs numbered 18279,18280,18281,\cdots,475253,475254 were respectively given the names aaaa, aaab, aaac, ..., zzzy, zzzz;

the dogs numbered 475255,475256,\cdots were respectively given the names aaaaa, aaaab, ...;

and so on.

To sum it up, the dogs numbered 1, 2, \cdots were respectively given the following names:

a, b, ..., z, aa, ab, ..., az, ba, bb, ..., bz, ..., za, zb, ..., zz, aaa, aab, ..., aaz, aba, abb, ..., abz, ..., zzz, aaaa, ...

Now, Roger asks you:

"What is the name for the dog numbered N?"

Constraints

N is an integer.

1 \leq N \leq 1000000000000001

Input

Input is given from Standard Input in the following format:

N

Output

Print the answer to Roger's question as a string consisting of lowercase English letters.

Sample Input 1

2

Sample Output 1

b

Sample Input 2

27

Sample Output 2

aa

Sample Input 3

123456789

Sample Output 3

jjddja

Solution in Python (3.8.2) (judge verdict: Wrong Answer)

N = int(input())
ans = ""
while True:
    rm = N % 26
    N //= 26
    if rm == 1:
        letter = "a"
    elif rm == 2:
        letter = "b"
    elif rm == 3:
        letter = "c"
    elif rm == 4:
        letter = "d"
    elif rm == 5:
        letter = "e"
    elif rm == 6:
        letter = "f"
    elif rm == 7:
        letter = "g"
    elif rm == 8:
        letter = "h"
    elif rm == 9:
        letter = "i"
    elif rm == 10:
        letter = "j"
    elif rm == 11:
        letter = "k"
    elif rm == 12:
        letter = "l"
    elif rm == 13:
        letter = "m"
    elif rm == 14:
        letter = "n"
    elif rm == 15:
        letter = "o"
    elif rm == 16:
        letter = "p"
    elif rm == 17:
        letter = "q"
    elif rm == 18:
        letter = "r"
    elif rm == 19:
        letter = "s"
    elif rm == 20:
        letter = "t"
    elif rm == 21:
        letter = "u"
    elif rm == 22:
        letter = "v"
    elif rm == 23:
        letter = "w"
    elif rm == 24:
        letter = "x"
    elif rm == 25:
        letter = "y"
    elif rm == 0:
        letter = "z"
    ans = f"{letter}{ans}"
    if N == 0:
        break
print(ans)