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.

Examples

Input

2


Output

b


Input

27


Output

aa


Input

123456789


Output

jjddja
import java.util.*;
import java.util.function.*;
import java.math.*;
public class Main {
    public static void main(String[] args){
		Scanner s = new Scanner(System.in);
		long N = Long.valueOf(s.next());
		
		char[] ret;
		
		int keta = 0;
		long now = 1;
		while(true) {
			now *= 26;
			keta++;
			if(N <= now) {
				ret = new char[keta];
				N--;
				for(int i = 0; i < keta; i++) {
					ret[keta-i-1] = (char)(N%26 + 'a');
					N /= 26;
				}
				break;
			}else {
				N -= now;
			}
		}
		System.out.println(new String(ret));
	}
}