p02629 AtCoder Beginner Contest 171 - One Quadrillion and One Dalmatians
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
```python
n = int(input())
s = ''
while n > 0:
    n -= 1
    s = chr(ord('a') + n % 26) + s
    n //= 26
print(s)
```