JS题解LeetCode1051高度检查器：哈希表与排序对比

/**
 * @param {number[]} heights
 * @return {number}
 */
var heightChecker = function (heights) {
  const arr = new Array(100).fill(0)
  let t = 0
  let idx = 101
  heights.forEach(item => {
    arr[item]++
    if (item < idx) idx = item
  })
  heights.forEach(item => {
    if (item !== idx) {
      t++
    }
    arr[idx]--
    while (arr[idx] === 0) {
      idx++
    }
  })
  return t
};
​​​​​​​var heightChecker = function (heights) {
  const h = JSON.parse(JSON.stringify(heights))
  const arr = heights.sort((a, b) => a - b)
  let t = 0
  for (let i = 0; i < arr.length; i++) {
    if (arr[i] !== h[i]) t++
  }
  return t
};