I figured it out! Sort of on my own, sort of studying how others had “solved” it in different languages (a few of the “solutions” didn’t seem to work). Array Addition I is now my bitch. Also the next 10 easy problems from Coderbyte are on my GitHub. 6 more to go (well 7 actually, I gave up on ArithGeo, but the solving of Array Addition gives me hope that I will figure it out tomorrow). Problem description: Using the JavaScript language, have the function ArrayAdditionI(arr) take the array of numbers stored in arr and return the string true if any combination of numbers in the array can be added up to equal the largest number in the array, otherwise return the string false. For example: if arr contains [4, 6, 23, 10, 1, 3] the output should return true because 4 + 6 + 10 + 3 = 23. The array will not be empty, will not contain all the same elements, and may contain negative numbers. And my solution: (basically grabs the largest value out of a provided array and it runs through all the possible sum combinations of all the other numbers to see if one of those sums equals the largest values)

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function ArrayAdditionI(arr) {
  arr.sort(function(a,b){return a - b})
  var largest = arr.pop();
  var sum = 0;

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

    for (var j = 0; j < arr.length; j++){
      if (i != j) {
        sum += arr[j];
        if (sum == largest) {
          return true;
        }
      }
    }

    for (var k = 0; k < arr.length; k++) {
      if (i != k) {
        sum -= arr[k];
        if (sum == largest) {
          return true;
        }
      }
    }

    sum = 0;
  }

  return false;
}