181897

function solution(n, slicer, num_list) {
  let [a, b, c] = [...slicer];
 
  switch (n) {
    case 1:
      return num_list.slice(0, b + 1);
    case 2:
      return num_list.slice(a);
    case 3:
      return num_list.slice(a, b + 1);
    case 4:
      return num_list.slice(a, b + 1).filter((_, idx) => !(idx % c));
  }
}

const slices = {
  1: (num_list, [a, b, c]) => num_list.slice(0, b + 1),
  2: (num_list, [a, b, c]) => num_list.slice(a),
  3: (num_list, [a, b, c]) => num_list.slice(a, b + 1),
  4: (num_list, [a, b, c]) =>
    num_list.slice(a, b + 1).filter((_, i) => i % c === 0),
};
 
function solution(n, slicer, num_list) {
  return slices[n](num_list, slicer);
}