how to store array data in nested array in javascript code example

Example 1: js array two dimensional

// declaration of a two-dimensional array
// 5 is the number of rows and 4 is the number of columns.
const matrix = new Array(5).fill(0).map(() => new Array(4).fill(0));

console.log(matrix[0][0]); // 0

Example 2: nested array loop in javascript

let chunked = [[1,2,3], [4,5,6], [7,8,9]];

for(let i = 0; i < chunked.length; i++) {
  
   for(let j = 0; j < chunked[i].length; j++) {
     
      console.log(chunked[i][j]);
   }
}