Sum All Numbers in a Range

helpfulStuff.js

function sumAll(arr) {
  var sum = 0;
  
  var maxNum = Math.max.apply(null, arr);
  var minNum = Math.min.apply(null, arr);
  
  console.log(maxNum);
  console.log(minNum);
  
  for(var i = minNum; i <= maxNum; i++){
    sum = parseInt(sum + i);
  }
  return sum;
}

sumAll([1, 4]);