CF1511D.Min Cost String

Let's define the cost of a string $s$ as the number of index pairs $i$ and $j$ ($1 \le i \lt j \lt |s|$) such that $s_i = s_j$ and $s_{i+1} = s_{j+1}$.

You are given two positive integers $n$ and $k$. Among all strings with length $n$ that contain only the first $k$ characters of the Latin alphabet, find a string with minimum possible cost. If there are multiple such strings with minimum cost — find any of them.

我们定义字符串 $s$ 的代价为满足以下条件的下标对 $(i, j)$ 的数量：$1 \le i \lt j \lt |s|$，且 $s_i = s_j$ 以及 $s_{i+1} = s_{j+1}$。

给定两个正整数 $n$ 和 $k$。在所有长度为 $n$、且仅由拉丁字母表前 $k$ 个字符组成的字符串中，找出一个代价最小的字符串。若存在多个代价最小的字符串，则输出任意一个即可。

The only line contains two integers $n$ and $k$ ($1 \le n \le 2 \cdot 10^5; 1 \le k \le 26$).

唯一一行包含两个整数 $n$ 和 $k$（$1 \le n \le 2 \cdot 10^5$；$1 \le k \le 26$）。

Print the string $s$ such that it consists of $n$ characters, each its character is one of the $k$ first Latin letters, and it has the minimum possible cost among all these strings. If there are multiple such strings — print any of them.

输出字符串 $s$，要求其长度为 $n$，且每个字符均来自前 $k$ 个拉丁字母，并在所有满足条件的字符串中具有最小可能的代价。若存在多个满足条件的字符串，则输出其中任意一个即可。