Nesting For Loops - antoniojvargas/FreeCodeCamp GitHub Wiki

Nesting For Loops

If you have a multi-dimensional array, you can use the same logic as the prior waypoint to loop through both the array and any sub-arrays. Here is an example:

var arr = [
  [1,2], [3,4], [5,6]
];
for (var i=0; i < arr.length; i++) {
  for (var j=0; j < arr[i].length; j++) {
    console.log(arr[i][j]);
  }
}

This outputs each sub-element in arr one at a time. Note that for the inner loop, we are checking the .length of arr[i], since arr[i] is itself an array. Instructions

Modify function multiplyAll so that it multiplies the product variable by each number in the sub-arrays of arr

function multiplyAll(arr) {
  var product = 1;
  // Only change code below this line
  for (var i=0; i < arr.length; i++) {
	for (var j=0; j < arr[i].length; j++) {
	  console.log(arr[i][j]);
	  product *= arr[i][j];
	}
  }
  // Only change code above this line
  return product;
}

// Modify values below to test your code
multiplyAll([1,2],[3,4],[5,6,7](/antoniojvargas/FreeCodeCamp/wiki/1,2],[3,4],[5,6,7));