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 Go (1.14.1) (judge verdict: Accepted)

package main

import (
	"fmt"
	"strings"
)

var LowerAlphabets = [...]string{"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"}

var AlphabetNumberMap = map[string]int{
	"a": 10,
	"b": 11,
	"c": 12,
	"d": 13,
	"e": 14,
	"f": 15,
	"g": 16,
	"h": 17,
	"i": 18,
	"j": 19,
	"k": 20,
	"l": 21,
	"m": 22,
	"n": 23,
	"o": 24,
	"p": 25,
	"q": 26,
}

func main() {
	var n int
	fmt.Scan(&n)
	var names []string
	for n > 26 {
		names = append([]string{LowerAlphabets[((n - 1) % 26)]}, names...)
		n = (n-1) / 26
	}
	names = append([]string{LowerAlphabets[((n - 1) % 26)]}, names...)
	fmt.Println(strings.Join(names, ""))
}