what is syntax to write 2d array in javascript code example

Example 1: how to make a 2d array in js

let x = [
  [1, 2, 3],
  [4, 5, 6],
  [7, 8, 9]
];
console.log(items[0][0]); // 1
console.log(items[0][1]); // 2
console.log(items[1][0]); // 4
console.log(items[1][1]); // 5
console.log(items);

Example 2: creating 2d array in javascript

var [r, c] = [5, 5]; 
var m = Array(r).fill().map(()=>Array(c).fill(0));