Return Largest Numbers in Arrays

Taking this step by step.

First to get the largest number in an array

function largestOfFour(arr) {
  // You can do this!
  for(i=0;i<arr.length;i++){
  var largest = 0;
  if(arr[i]>largest){
  largest = arr[i];
  }
  return largest;
  }
  return arr;
}

largestOfFour([4, 5, 1, 3]);


Second Step:

function largestOfFour(arr) {
  // You can do this!
   for(i =0 ; i <arr[i].length; i++){

//The trick is to assign the largest variable correctly.
     var largest = 0;
     for(k=0;k<4;k++){
       if(arr[i][k] > largest){
        largest = arr[i][k];
       }
     }
    console.log(largest);
   }
  return arr;
}

largestOfFour([[4, 5, 1, 3], [13, 27, 18, 26], [32, 35, 37, 39], [1000, 1001, 857, 1]]);


Finally


function largestOfFour(arr) {
  // You can do this!
   var newarray = [];

  for (var i = 0; i < arr.length; i++){

     var largest = [];
     for(k=0;k<4;k++){
       if(arr[i][k] > largest){
        largest = arr[i][k];
       }
     }
     newarray[i] = largest;
     }
 return newarray;
}

largestOfFour([[4, 5, 1, 3], [13, 27, 18, 26], [32, 35, 37, 39], [1000, 1001, 857, 1]]);