三路快速排序

// 快速排序
function quickSort(arr) {if (arr.length <= 1) {return arr;}const pivot = arr[0];const left = [];const right = [];for (let i = 1; i < arr.length; i++) {if (arr[i] < pivot) {left.push(arr[i]);} else {right.push(arr[i]);}}return quickSort(left).concat(pivot, quickSort(right));
}console.time('quickSort');
console.log(quickSort([0, 1, 0, 2, 0, 2, 1, 0, 1]));
console.timeEnd('quickSort');/* 三路排序算法
*/
function threeWaySort(arr) {// 三路排序算法let zero = 0,two = arr.length - 1;for (let i = 0; i < arr.length; i++) {while (arr[i] === 2 && i < two) {[arr[i], arr[two]] = [arr[two], arr[i]];two--;}if (arr[i] === 0) {[arr[i], arr[zero]] = [arr[zero], arr[i]];zero++;}}return arr;
}console.time('threeWaySort');
console.log(threeWaySort([0, 1, 0, 2, 0, 2, 1, 0, 1]));
console.timeEnd('threeWaySort');