You are given two positive integers n and k.

In a single operation, you can choose any bit in the binary representation of n that is equal to $1$ and change it to $0$.

Return the number of operations needed to make n equal to k. If it is impossible to make n equal to k, return $-1$.

Constraints:

• $1 \leq$ n, k $\leq 10^6$

Now, let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:

We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.

Implement your solution in the following coding playground.