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.*;
public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    long n = sc.nextLong();
    List<Integer> li = new ArrayList<Integer>();
    while(n != 0){
      int nn = (int)n % 26;
      li.add(nn);
      n /= 26;
      if(nn == 0 && n == 1){
        break;
      }
    }
    int size = li.size();
    for(int i = size -1;i>=0;i--){
      if(li.get(i) == 1){
        System.out.print("a");
      }else if (li.get(i) == 2){
        System.out.print("b");
      }else if (li.get(i) == 3){
        System.out.print("c");
      }else if (li.get(i) == 4){
        System.out.print("d");
      }else if (li.get(i) == 5){
        System.out.print("e");
      }else if (li.get(i) == 6){
        System.out.print("f");
      }else if (li.get(i) == 7){
        System.out.print("g");
      }else if (li.get(i) == 8){
        System.out.print("h");
      }else if (li.get(i) == 9){
        System.out.print("i");
      }else if (li.get(i) == 10){
        System.out.print("j");
      }else if (li.get(i) == 11){
        System.out.print("k");
      }else if (li.get(i) == 12){
        System.out.print("l");
      }else if (li.get(i) == 13){
        System.out.print("m");
      }else if (li.get(i) == 14){
        System.out.print("n");
      }else if (li.get(i) == 15){
        System.out.print("o");
      }else if (li.get(i) == 16){
        System.out.print("p");
      }else if (li.get(i) == 17){
        System.out.print("q");
      }else if (li.get(i) == 18){
        System.out.print("r");
      }else if (li.get(i) == 19){
        System.out.print("s");
      }else if (li.get(i) == 20){
        System.out.print("t");
      }else if (li.get(i) == 21){
        System.out.print("u");
      }else if (li.get(i) == 22){
        System.out.print("v");
      }else if (li.get(i) == 23){
        System.out.print("w");
      }else if (li.get(i) == 24){
        System.out.print("x");
      }else if (li.get(i) == 25){
        System.out.print("y");
      }else if (li.get(i) == 0){
        System.out.print("z");
      }
    }
    System.out.println("");
  }
}