Sum All Numbers in a Range. Can't create an array of all numbers in the range using a for loop

Tell us what’s happening:

So my game plan here was to sort the two numbers in ascending order, then make an array of all the numbers between the two given numbers via a for loop, then add all those together using arr.reduce. I read the solution in the meantime and realize there’s a better way to do it, but I can’t figure out why my solution isn’t working. My attempted solution gave me an infinite loop warning, and I can’t seem to figure out why. I tried both a for and while loop and got the same error. There’s probably something super obvious I’m missing, but I can’t seem to hammer it down. Can someone set me straight? Here was my attempt:

Side note, I was having the function return inbetween in a debugging attempt.

Your code so far

function sumAll(arr) {
  arr.sort(function(a, b){return a-b}); 
  const inbetween = []

for (i=0; arr[0] < i < arr[1]; i++){

  return inbetween;

sumAll([1, 4]);

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**Link to the challenge:**

Try adding “let” before you use the i in the for loop…

Also why not start with i=arr[0] and loop for i<=arr[arr.length-1]

This is not a valid expression. If you want to compare two things to i, you have to write them separately like:

arr[0] < i && i < arr[1];