Each kind of piece moves in a pattern. A knight has 8 fixed jumps, each written as [rows, columns]. A jump is only
possible if it lands on the board, so we also write inside(r, c).
```js
const KNIGHT = [[1, 2], [2, 1], [2, -1], [1, -2], [-1, -2], [-2, -1], [-2, 1], [-1, 2]]
const inside = (r, c) => r >= 0 && r < 8 && c >= 0 && c < 8
```
What it means
KNIGHT is an array of 8 small arrays: the row and column difference of each jump.
inside is a short arrow function; && means "and", so all four conditions must hold. It returns true or
false.
Your turn
Under the START line write KNIGHT.
Under the closing } of reset, leave an empty line and write inside.