1
var topKFrequent = function (nums, k) {
2
  let store = {};
3
  for (let i = 0; i < nums.length; i++) {
4
    store[nums[i]] = store[nums[i]] + 1 || 1;
5
  }
6
  //returns an array of keys in sorted order
7
  let keyArr = Object.keys(store).sort((a, b) => store[a] - store[b]);
8
  let arrLength = keyArr.length;
9
  let slicedArr = keyArr.slice(arrLength - k, arrLength);
10
  return slicedArr;
11
};