Several classic sorting algorithms.
- Bubble Sort
function bubble(arr, n) {
for (let i = 0; i < n - 1; i++) {
if (arr[i] > arr[i + 1]) {
let temp = arr[i]
arr[i] = arr[i + 1]
arr[i + 1] = temp
}
}
}
function bubbleSort(arr) {
for (let i = arr.length; i > 1; i--) {
bubble(arr, i)
}
}
let arr = [9, 8, 7, 6, 5, 4, 3, 2, 1]
bubbleSort(arr)
console.log(arr)
- Selection Sort
function findMaxPosition(arr, n) {
let pos = 0
let max = arr[pos]
for (let i = 0; i < n; i++) {
if (arr[i] > max) {
max = arr[i]
pos = i
}
}
return pos
}
function selectionSort(arr) {
for (let i = arr.length; i > 1; i--) {
let pos = findMaxPosition(arr, i)
let temp = arr[pos]
arr[pos] = arr[i - 1]
arr[i - 1] = temp
}
}
let arr = [0, 3, 4, 5, 7, 9, 8, 10, 1, 2]
selectionSort(arr)
console.log(arr)
- Insert Sort
function insert(arr, n) {
let pos = n - 1
let key = arr[pos]
for (; key < arr[pos - 1] && pos > 0; pos--) {
arr[pos] = arr[pos - 1]
}
arr[pos] = key
}
function insertSort(arr) {
for (let i = 2; i <= arr.length; i++) {
insert(arr, i)
}
}
let arr = [3, 6, 7, 4, 2, 1, 5]
insertSort(arr, arr.length)
console.log(arr)
- Shell Sort
function shellSort(arr) {
for (let gap = Math.floor(arr.length / 2); gap > 0; gap = Math.floor(gap / 2)) {
for (let i = gap; i < arr.length; i++) {
let pos = i
let key = arr[pos]
for (; pos > 0 && arr[pos - gap] > key; pos -= gap) {
arr[pos] = arr[pos - gap]
}
arr[pos] = key
}
}
}
let arr = [15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 100, 0, -1, 22, 23]
shellSort(arr)
console.log(arr)
- Merge Sort
function merge(arr, l, m, r) {
let arrL = arr.slice(l, m)
let arrR = arr.slice(m, r + 1)
let i = 0
let j = 0
let k = l
for (; i < arrL.length && j < arrR.length; k++) {
if (arrL[i] < arrR[j]) {
arr[k] = arrL[i]
i += 1
} else {
arr[k] = arrR[j]
j += 1
}
}
for (; i < arrL.length; i++ & k++) {
arr[k] = arrL[i]
}
for (; j < arrR.length; j++ & k++) {
arr[k] = arrR[j]
}
}
function mergeSort(arr, l, m, r) {
if (r > l) {
mergeSort(arr, l, Math.floor((l + m) / 2), m - 1)
mergeSort(arr, m, Math.floor((m + r + 1) / 2), r)
merge(arr, l, m, r)
}
}
let arr = [0, 2, 4, 6, 8, 1, 3, 5, 7, 9, 100, 55]
mergeSort(arr, 0, Math.floor(arr.length / 2), arr.length - 1)
console.log(arr)
- Quick Sort
function partition(arr, l, r) {
let pivot = arr[r]
let pos = l
for (let i = l; i < r; i++) {
if (arr[i] < pivot) {
let temp = arr[i]
arr[i] = arr[pos]
arr[pos] = temp
pos += 1
}
}
arr[r] = arr[pos]
arr[pos] = pivot
return pos
}
function quickSort(arr, l, r) {
if (r > l) {
let pos = partition(arr, l, r)
quickSort(arr, l, pos - 1)
quickSort(arr, pos + 1, r)
}
}
let arr = [9, 3, 8, 1, 2, 100, 5, 4, 0, 6, 7]
quickSort(arr, 0, arr.length - 1)
console.log(arr)
- Heap Sort
function heapify(arr, size, i) {
let maxIndex = i
let left = 2 * i + 1
let right = 2 * i + 2
if (left < size && arr[left] > arr[maxIndex]) {
maxIndex = left
}
if (right < size && arr[right] > arr[maxIndex]) {
maxIndex = right
}
if (maxIndex !== i) {
let temp = arr[maxIndex]
arr[maxIndex] = arr[i]
arr[i] = temp
heapify(arr, size, maxIndex)
}
}
function maxHeap(arr, size) {
for (let i = Math.floor(size / 2) - 1; i >= 0; i--) {
heapify(arr, size, i)
}
}
function heapSort(arr) {
for (let i = arr.length; i > 1; i--) {
maxHeap(arr, i)
let temp = arr[i - 1]
arr[i - 1] = arr[0]
arr[0] = temp
}
}
let arr = [9, 3, 8, 1, 2, 100, 5, 4, 0, 6, 7, 55, 66, 44]
heapSort(arr)
console.log(arr)