一.快速排序
function qSort(arr) {
if(arr.length === 0) {
return [];
}
var left = [];
var right = [];
var pivot = arr[0];
for (var i = 1; i < arr.length; i++) {//从i=1开始
if(arr[i] < pivot) {
left.push(arr[i]);
}else {
right.push(arr[i]);
}
}
return qSort(left).concat(pivot, qSort(right));
}//快速排序
window.onload = function() {
var a = [];
for (var i = 0; i < 10; ++i) {
a[i] = Math.floor((Math.random()*100)+1);
}
console.log(a);
console.log(qSort(a));//快速排序
}
二.插入排序
function insertionSort(arr) {
var temp, inner;
console.log(arr);
for(var outer = 1; outer < arr.length; outer++) {
temp = arr[outer];
inner = outer;
while(inner > 0 && (arr[inner - 1] >= temp)) {
arr[inner] = arr[inner - 1];
inner--;
}
arr[inner] = temp;
}
return arr;
}//插入排序
window.onload = function() {
var a = [];
for (var i = 0; i < 10; ++i) {
a[i] = Math.floor((Math.random()*100)+1);
}
console.log(a);
console.log(insertionSort(a));//插入排序
}
三.选择排序法
function selectionSortMax(arr) {
var max;
for(var outer = 0; outer < arr.length; outer++) {
max = 0;
for(var inner = 0; inner < arr.length - outer; inner++) {
if(arr[inner] > arr[max]) {
max = inner;
}
}
swap(arr, max, arr.length - outer - 1);
}
return arr;
}//选择排序法选择最大值移到最后
function selectionSortMin(arr) {
var min, temp;
for(var outer = 0; outer < arr.length - 1; outer++) {
min = outer;
for(var inner = outer + 1; inner < arr.length; inner++) {
if(arr[inner] < arr[min]) {
min = inner;
}
}
swap(arr, min, outer);
}
return arr;
}//选择排序法选择最小值移到最前
function swap(arr, index1, index2) {
var temp = arr[index2];
arr[index2] = arr[index1];
arr[index1] = temp;
}
window.onload = function() {
var a = [];
for (var i = 0; i < 10; ++i) {
a[i] = Math.floor((Math.random()*100)+1);
}
console.log(a);
console.log(selectionSortMax(a));
console.log(selectionSortMin(a));
}
四.冒泡排序法
function bubbleSort(arr) {
var temp;
for(var outer = arr.length; outer > 1; outer--) {
for(inner = 0; inner < outer - 1; inner++) {
if(arr[inner] > arr[inner + 1]) {
swap(arr, inner, inner + 1);
}
}
}
return arr;
}//冒泡排序法
function swap(arr, index1, index2) {
var temp = arr[index2];
arr[index2] = arr[index1];
arr[index1] = temp;
}
window.onload = function() {
var a = [];
for (var i = 0; i < 10; ++i) {
a[i] = Math.floor((Math.random()*100)+1);
}
console.log(a);
console.log(bubbleSort(a));//冒泡排序法
}
五.归并算法
function mergeSortRec(array) {
var length = array.length;
if(length == 1) {
return array;
}
var mid = Math.floor(length / 2);
var left = array.slice(0, mid);
var right = array.slice(mid, length);
return merge(mergeSortRec(left), mergeSortRec(right));
}
function merge(left, right) {
var result = [];
var il = 0;
var ir = 0;
while(il < left.length && ir < right.length) {
if(left[il] < right[ir]) {
result.push(left[il++]);
}else {
result.push(right[ir++]);
}
}
while(il < left.length) {
result.push(left[il++]);
}
while(ir < right.length) {
result.push(right[ir++]);
}
return result;
}
window.onload = function() {
var a = [];
for (var i = 0; i < 10; ++i) {
a[i] = Math.floor((Math.random()*100)+1);
}
console.log(a);
console.log(mergeSortRec(a));//归并排序法
}
通过时间戳可以得到快速排序>选择排序>插入排序>冒泡排序。