CodePen Home LeetCode 347 bucket sort

leetCode347.js

var topKFrequent = function(nums, k) {
    let hash = {}
    nums.forEach(row => {
      if(hash[row] === undefined) {
        hash[row] = 1;
      }else {
        hash[row] += 1;
      }
    })
  let res = [...hash].sort((a,b) => a[1]-b[1])
  //object can't iterator directory
  console.log(res)
};

var topKFrequent2 = function(nums, k) {
    let hash = new Map();
    nums.forEach(row => {
      if(hash.has(row)) {
        hash.set(row,hash.get(row)+1);
      }else {
         hash.set(row,1);
      }
    })
  console.log('hash key sort:');
  for (var key of hash.keys()) {
    console.log(key);
  }
  let res = [...hash].sort((a,b) => b[1]-a[1])
  res = res.map(item => item[0])
  return res.slice(0,k)
};
const nums = [1,1,1,2,2,4], k = 2
console.log(topKFrequent2(nums,k))