排序

1. 快速排序

// 快速排序
let arr =[ { id: 1, score: 10 },  { id: 2, score: 5 },  { id: 3, score: 14 }];

let lessFunc = function(a, b) {
   return a.score <= b.score;
};
let kuaisu = function(arr, lessFunc) {
  const quickSort = function(arr, low, high) {
    let i = low;
    let j = high;
    let pivot = arr[low];
    if (i >= j) {
      return;
    }
    while (i != j) {
      while (i < j && lessFunc(pivot, arr[j])) j--;
      if (i < j) arr[i] = arr[j];
      while (i < j && lessFunc(arr[i], pivot)) i++;
      if (i < j) arr[j] = arr[i];
    }
    arr[i] = pivot;
    quickSort(arr, low, i - 1);
    quickSort(arr, i + 1, high);
  };
  quickSort(arr, 0, arr.length - 1);
  return arr;
};

2. 冒泡排序

es6

for(let i in array) {
  for(let j in array) {
    if(array[j]> array[i]) {
      /* 交换 */
      let tmp = array[i];
      array[i] = array[j];
      array[j] = tmp;
    }
  }
}

es5

for(var i in array) {
  for(var j in array) {
    if(array[j]> array[i]) {
      /* 交换 */
      var tmp = array[i];
      array[i] = array[j];
      array[j] = tmp;
    }
  }
}