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 Java (OpenJDK 11.0.6) (judge verdict: Wrong Answer)

import java.util.*;
import static java.lang.Math.*;

class Main {
    final Scanner sc = new Scanner(System.in);

    public static void main(String[] args) {
        new Main().run();
    }

    private void run() {
        long n = sc.nextLong();
        int[] m = new int[100];
        Arrays.fill(m, -1);
        for (int i = 1; i < 100; i++) {
            m[i] = (int)(n % 26);
            n = n / 26;
            if (n == 0) {
                break;
            }
        }

        for (int i = 99; i > 0; i--) {
            switch (m[i]) {
                case -1:
                    break;
                case 1:
                    System.out.print("a");
                    break;
                case 2:
                    System.out.print("b");
                    break;
                case 3:
                    System.out.print("c");
                    break;
                case 4:
                    System.out.print("d");
                    break;
                case 5:
                    System.out.print("e");
                    break;
                case 6:
                    System.out.print("f");
                    break;
                case 7:
                    System.out.print("g");
                    break;
                case 8:
                    System.out.print("h");
                    break;
                case 9:
                    System.out.print("i");
                    break;
                case 10:
                    System.out.print("j");
                    break;
                case 11:
                    System.out.print("k");
                    break;
                case 12:
                    System.out.print("l");
                    break;
                case 13:
                    System.out.print("m");
                    break;
                case 14:
                    System.out.print("n");
                    break;
                case 15:
                    System.out.print("o");
                    break;
                case 16:
                    System.out.print("p");
                    break;
                case 17:
                    System.out.print("q");
                    break;
                case 18:
                    System.out.print("r");
                    break;
                case 19:
                    System.out.print("s");
                    break;
                case 20:
                    System.out.print("t");
                    break;
                case 21:
                    System.out.print("u");
                    break;
                case 22:
                    System.out.print("v");
                    break;
                case 23:
                    System.out.print("w");
                    break;
                case 24:
                    System.out.print("x");
                    break;
                case 25:
                    System.out.print("y");
                    break;
                case 0:
                    System.out.print("z");
                    break;
            }
        }
        System.out.println();
    }
}