JavaScript实现各种排序算法

function bubbleSort(arr) {console.time("冒泡排序")var num &＃61; 0;for (var i &＃61; arr.length; i > num; num&＃43;&＃43;) {for (var j &＃61; i - 1; j > num; j--) {if(arr[j-1]>arr[j]){var temp &＃61; arr[j-1];arr[j-1] &＃61; arr[j];arr[j] &＃61; temp;}}}console.timeEnd("冒泡排序")return arr}var arr &＃61; [12, 290, 219, 278, 4432,21, 43, 89, 78];console.log( bubbleSort(arr));

function insertSort(arr) {console.time("插入排序")var len &＃61; arr.length;if (len <&＃61; 1) {return arr;}// 1~n-1趟排序arr.map(function(item,index){if(index>0){for (var j &＃61; index; j > 0 && arr[j - 1] > item; j--) {arr[j] &＃61; arr[j - 1];}arr[j] &＃61; item;}});console.timeEnd("插入排序")return arr
}
var arr &＃61; [12, 290, 219, 278, 4432, 21, 43, 89, 78];
console.log(insertSort(arr));

12 190 219 278
4432 21 43 89
78
// 第一次排序之后得到&＃xff1a;
12 21 43 89
78 190 219 278
4432// 连接起来得到的是 [12&＃xff0c;21&＃xff0c;43&＃xff0c;89&＃xff0c;78&＃xff0c;190&＃xff0c;219&＃xff0c;278&＃xff0c;4432]&＃xff0c;接着以2为步长 排序之后变为:
12 21
43 89
78 190
219 278
4432// 然后就是简单的插入排序

1 function qSort(arr) {
2 if (arr.length <&＃61; 1) {
3 return arr;
4 }
5 var num &＃61; Math.floor(arr.length / 2);
6
7 var numValue &＃61; arr.splice(num, 1)[0];
8 var left &＃61; [],
9 right &＃61; [];
10 for (var i &＃61; 0; i ) {
11 if (arr[i] < numValue) {
12 left.push(arr[i]);
13 } else {
14 right.push(arr[i]);
15 }
16 }
17 return qSort(left)
18 .concat([numValue], qSort(right))
19 }
20
21 console.log(qSort([32, 45, 37, 16, 2, 87]))