Need help with Nesting For Loops

Tell us what’s happening:
I’m not looking for the answer, just need some help to get me going on this. I guess my first question is how exactly does a console.log work and do I need to use it for this challenge?

Your code so far

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

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

Your browser information:

Your Browser User Agent is: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.90 Safari/537.36.

Link to the challenge:
https://www.freecodecamp.org/challenges/nesting-for-loops

console.log() is a very useful tool for debugging your code. It allows you to check the state of something at any given time by printing (“logging”) it to the terminal.

Here’s a silly little example of how you can use it to keep track of what’s going on in your code:

How do you run console.log within the FCC challenges?

You will want to use your browser’s console by bringing up the dev tools.
Console and logging
Chrome Dev Tools: Console