JS Two-dimensional array

To an array element that assigns an array value, then the array is a "two-dimensional array".

Two-dimensional arrays, you have to use a double-layer loop to achieve. That is to say loop loops.

The loop of a two-dimensional array is exactly the same as that of a two-dimensional table.

access to two-dimensional arrays: array names followed by multiple consecutive brackets [] , the 1th brackets [] represents the first-dimensional array, 2nd brackets [] represents a second-dimensional array.

JS Two-dimensional array