4354: 新密码

Innokentiy decides to change the password in the social net "Contact!", but he is too lazy to invent a new password by himself. That is why he needs your help.
Innokentiy decides that new password should satisfy the following conditions:

• the length of the password must be equal to$n$,
• the password should consist only of lowercase Latin letters,
• the number of distinct symbols in the password must be equal to$k$,
• any two consecutive symbols in the password must be distinct.

Your task is to help Innokentiy and to invent a new password which will satisfy all given conditions.
因诺肯蒂决定在社交网络“Contact!”中更改密码，但他懒得自己发明新密码，所以他需要你的帮助。因诺肯蒂决定新密码应满足以下条件：

• 密码的长度必须等于$n$，
• 密码应仅由小写拉丁字母组成，
• 密码中不同字母的数量必须等于$k$，
• 密码中任意两个连续的字母必须是不同的。
• 你的任务是帮助因诺肯蒂并发明一个满足所有给定条件的新密码。

The first line contains two positive integers $ n $ and $ k $ ( $ 2 \leq n \leq100 $ , $ 2 \leq k\leq min(n,26) $ ) — the length of the password and the number of distinct symbols in it.

Pay attention that a desired new password always exists.

第一行包含两个正整数$n$和$k$（$2 \leq n \leq 100$，$2 \leq k \leq min(n，26)$）——密码的长度和其中不同字母的数量。

请注意，始终存在满足所需条件的新密码。

Print any password which satisfies all conditions given by Innokentiy.
打印任一满足因诺肯蒂给出的所有条件的密码。

样例输入 #1

4 3

样例输出 #1

java

样例输入 #2

6 6

样例输出 #2

python

样例输入 #3

5 2

样例输出 #3

phphp

提示

In the first test there is one of the appropriate new passwords — java, because its length is equal to $ 4 $ and $ 3 $ distinct lowercase letters a, j and v are used in it.

In the second test there is one of the appropriate new passwords — python, because its length is equal to $ 6 $ and it consists of $ 6 $ distinct lowercase letters.

In the third test there is one of the appropriate new passwords — phphp, because its length is equal to $ 5 $ and $ 2 $ distinct lowercase letters p and h are used in it.

Pay attention the condition that no two identical symbols are consecutive is correct for all appropriate passwords in tests.

在第一个测试中，其中一个合适的新密码——java，它的长度等于$4$，并且其中使用了$3$个不同的小写字母a，j和v。
在第二个测试中，其中一个合适的新密码——python，它的长度等于$6$，它由$6$个不同的小写字母组成。
在第三个测试中，其中一个合适的新密码——phphp，它的长度等于$5$并且其中使用了$2$个不同的小写字母p和h。
请注意，在测试中，没有两个相同的字母是连续的，对于所有合适的密码都是这样的。