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: Accepted)

process.stdin.resume();
process.stdin.setEncoding("utf8");
process.stdin.on("data", (input) => {
  const n = Number(input);

  const result = getResult(n);

  console.log(result);
});

const getResult = (n) => {
  let k = 1;
  let sum = 0;
  let result = convert(n);
  return result;
};

const convert = (value) => {
  let result = "";
  let div = value;
  let per = 0;
  do {
    const numbers = calculate(div);
    per = numbers.per;

    div = per === 0 ? numbers.div - 1 : numbers.div;
    result = convertNumToChar(per) + result;
  } while (div !== 0);
  return result;
};

const calculate = (num) => {
  const div = Math.floor(num / 26);
  const per = num % 26;
  return {
    div: div,
    per: per,
  };
};

const CHAR_CODE_0F_a = 97;

const convertNumToChar = (num) => {
  const offset = num > 0 ? num - 1 : 25;
  return String.fromCharCode(CHAR_CODE_0F_a + offset);
};