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 JavaScript (Node.js 12.16.1) (judge verdict: Wrong Answer)

const { isNumber } = require("util")

const input = require("fs").readFileSync("/dev/stdin", "utf8")
let cin = input.split(/ |\n/), cid = 0
const next = () => cin[cid++]
const nexts = (n) => cin.slice(cid, cid+=n).map(i=>parseInt(i))

const alphabet = [
    'a',
    'b',
    'c',
    'd',
    'e',
    'f',
    'g',
    'h',
    'i',
    'j',
    'k',
    'l',
    'm',
    'n',
    'o',
    'p',
    'q',
    'r',
    's',
    't',
    'u',
    'v',
    'w',
    'x',
    'y',
    'z'
]

const twentySix = [
    26,
    676,
    17576,
    456976,
    11881376,
    308915776,
    8031810176,
    208827064576,
    5429503678976,
    141167095653376
]

const N = parseInt(next())
array = N.toString(26).split('')
array = array.map(value => {
    if (value == parseInt(value)) {
        return parseInt(value)
    } else {
        return 9 + alphabet.indexOf(value) + 1
    }
})
if (twentySix.includes(N)) array = array.slice(1)
result = ''
array.forEach(i => {
    if (i == 0) {
        result += 'z'
    } else {
        result += alphabet[i-1]
    }
});
console.log(result)