quick sort algorithm

1#include<stdio.h>
2void quicksort(int number[25],int first,int last){
3   int i, j, pivot, temp;
4
5   if(first<last){
6      pivot=first;
7      i=first;
8      j=last;
9
10      while(i<j){
11         while(number[i]<=number[pivot]&&i<last)
12            i++;
13         while(number[j]>number[pivot])
14            j--;
15         if(i<j){
16            temp=number[i];
17            number[i]=number[j];
18            number[j]=temp;
19         }
20      }
21
22      temp=number[pivot];
23      number[pivot]=number[j];
24      number[j]=temp;
25      quicksort(number,first,j-1);
26      quicksort(number,j+1,last);
27
28   }
29}
30
31int main(){
32   int i, count, number[25];
33
34   printf("How many elements are u going to enter?: ");
35   scanf("%d",&count);
36
37   printf("Enter %d elements: ", count);
38   for(i=0;i<count;i++)
39      scanf("%d",&number[i]);
40
41   quicksort(number,0,count-1);
42
43   printf("Order of Sorted elements: ");
44   for(i=0;i<count;i++)
45      printf(" %d",number[i]);
46
47   return 0;
48}
49

1def partition(a,l,h):
2    pivot = a[l]
3    i = l
4    j=h
5    while i<j:
6        while a[i]<=pivot and i<h: i+=1
7        while a[j]>pivot and j>l: j-=1
8        if i<j: a[i],a[j]=a[j],a[i]
9        
10    a[j],a[l]=a[l],a[j]
11    return j
12
13def quickSort(a,l,h):
14    if l < h:
15        pi = partition(a, l, h)
16        quickSort(a, l, pi - 1)
17        quickSort(a, pi + 1, h)
18        
19#driver Code        
20a =[10, 7, 8, 9, 1, 5 ]
21quickSort(a, 0, len(a) - 1)
22print(a)
23#Output: [1, 5, 7, 8, 9, 10]

1// @see https://www.youtube.com/watch?v=es2T6KY45cA&vl=en
2// @see https://www.youtube.com/watch?v=aXXWXz5rF64
3// @see https://www.cs.usfca.edu/~galles/visualization/ComparisonSort.html
4
5function partition(list, start, end) {
6    const pivot = list[end];
7    let i = start;
8    for (let j = start; j < end; j += 1) {
9        if (list[j] <= pivot) {
10            [list[j], list[i]] = [list[i], list[j]];
11            i++;
12        }
13    }
14    [list[i], list[end]] = [list[end], list[i]];
15    return i;
16}
17
18function quicksort(list, start = 0, end = undefined) {
19    if (end === undefined) {
20        end = list.length - 1;
21    }
22    if (start < end) {
23        const p = partition(list, start, end);
24        quicksort(list, start, p - 1);
25        quicksort(list, p + 1, end);
26    }
27    return list;
28}
29
30quicksort([5, 4, 2, 6, 10, 8, 7, 1, 0]);
31

1//last element selected as pivot
2#include <iostream>
3
4using namespace std;
5void swap(int*,int*);
6int partition(int arr[],int start,int end)
7{
8    int pivot=arr[end];
9    int index=start;
10    int i=start;
11    while(i<end)
12    {
13        if(arr[i]<pivot)
14        {
15            swap(&arr[index],&arr[i]);
16            index++;
17        }
18        i++;
19    }
20    swap(&arr[end],&arr[index]);
21    return index;
22}
23void quicksort(int arr[],int start,int end)
24{
25    if(start<end)
26    {
27      int pindex=partition(arr,start,end);
28      quicksort(arr,start,pindex-1);
29      quicksort(arr,pindex+1,end);
30    }
31}
32void display(int arr[],int n)
33{
34    for(int i=0;i<n;i++)
35    {
36        cout<<arr[i]<<" ";
37    }
38    cout<<endl;
39}
40
41int main()
42{
43    int n;
44    cout<<"enter the size of the array:"<<endl;
45    cin>>n;
46    int arr[n];
47    cout<<"enter the elements of the array:"<<endl;
48    for(int i=0;i<n;i++)
49    {
50        cin>>arr[i];
51    }
52    cout<<"sorted array is:"<<endl;
53    quicksort(arr,0,n-1);
54    display(arr,n);
55
56    return 0;
57}
58void swap(int *a,int*b)
59{
60    int temp=*a;
61    *a=*b;
62    *b=temp;
63}
64

1// A full c++ quicksort algorithm no bs
2// quicksort in code
3
4#include <iostream>
5
6using namespace std;
7
8void QuickSort(int arr[], int start, int end);
9int Partition(int arr[], int start, int end);
10void SwapArrMem(int arr[], int a, int b);
11
12int main()
13{
14
15	int arr[4]; //change the size of the array to your desired array size
16
17	cout << "enter " << sizeof(arr) / sizeof(arr[0]) << " numbers. press enter after input" << endl;
18
19	for (int i = 0; i < sizeof(arr) / sizeof(arr[0]); i++)
20	{
21		
22		cin >> arr[i];
23	}
24
25	cout << endl << "The sorted numbers are:" << endl << endl;
26
27
28
29	QuickSort(arr, 0, sizeof(arr) / sizeof(arr[0]) - 1);
30
31	for (int i = 0; i < sizeof(arr) / sizeof(arr[0]); i++)
32	{
33		cout << arr[i] << endl;
34	}
35
36}
37
38void QuickSort(int arr[], int start, int end)
39{
40	if (start >= end) return;
41
42	int index = Partition(arr, start, end);
43	QuickSort(arr, start, index - 1);
44	QuickSort(arr, index + 1, end);
45}
46
47int Partition(int arr[], int start, int end)
48{
49	int pivotindex = start;
50	int pivotvalue = arr[end];
51	for (int i = start; i < end; i++)
52	{
53		if (arr[i] < pivotvalue)
54		{
55			SwapArrMem(arr, i, pivotindex);
56			pivotindex++;
57		}
58	}
59	SwapArrMem(arr, pivotindex, end);
60	return pivotindex;
61}
62
63void SwapArrMem(int arr[], int a, int b)
64{
65	int temp = arr[a];
66	arr[a] = arr[b];
67	arr[b] = temp;
68} 

1n*log(n)