Return an array consisting of the largest number from each provided sub-array.

Return Largest Numbers in Arrays

function largestOfEachSubarray(r) {
  for (i = 0; i < r.length; i++) {
    var a = r[i],
      n = 0;
    for (j = 0; j < a.length; j++) {
      var t = a[j];
      n < t && (n = t)
    }
    r[i] = n
  }
  return r
}