You are given a $2$D integer grid grid of size m $ imes$ n, and an integer x.

In one operation, you can choose any element in grid and either add x to it or subtract x from it.

A grid is considered uni value if all of its elements are equal.

Return the minimum number of operations needed to make grid uni value. If it is impossible to make all elements equal, return $-1$.

Constraints:

• m $==$ grid.length

• n $==$ grid[i].length

• $1 \leq$ m, n $\leq 10^5$

• $1 \leq$ m $ imes$ n $\leq 10^5$

• $1 \leq$ x, grid[i][j] $\leq 10^4$

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.