1328F · Make k Equal

Problem: You are given the array $a$ consisting of $n$ elements and the integer $k \le n$.

You want to obtain at least $k$ equal elements in the array $a$. In one move, you can make one of the following two operations:

• Take one of the minimum elements of the array and increase its value by one (more formally, if the minimum value of $a$ is $mn$ then you choose such index $i$ that $a_i = mn$ and set $a_i := a_i + 1$);
• take one of the maximum elements of the array and decrease its value by one (more formally, if the maximum value of $a$ is $mx$ then you choose such index $i$ that $a_i = mx$ and set $a_i := a_i - 1$).

Your task is to calculate the minimum number of moves required to obtain at least $k$ equal elements in the array.

Input Format: The first line of the input contains two integers $n$ and $k$ ($1 \le k \le n \le 2 \cdot 10^5$) — the number of elements in $a$ and the required number of equal elements.

The second line of the input contains $n$ integers $a_1, a_2, \dots, a_n$ ($1 \le a_i \le 10^9$), where $a_i$ is the $i$-th element of $a$.

Output Format: Print one integer — the minimum number of moves required to obtain at least $k$ equal elements in the array.