nested_for_loop.js

/* 
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++) {
  	console.log(arr[i]);
  	for (var j = 0; j < arr[i].length; j++) {
  		console.log(arr[i][j]);
  		console.log(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]]);