Eloquent-Ch-7

To store a grid of values, we have several options. We can use an array of row arrays and use two property accesses to get to a specific square, like this:

var grid = [["top left", "top middle", "top right"], ["bottom left", "bottom middle", "bottom right"]];
console.log(grid[1][2]);

// . bottom right

Or we can use a single array, with size width × height, and decide that

the element at (x,y) is found at position x + (y × width) in the array.

var grid = ["top left", "top middle", "top right", "bottom left", "bottom middle", "bottom right"];
console.log(grid[2 + (1 * 3)]);

// . bottom right