Example 1: quick sort program in c
#include<stdio.h>
void quicksort(int number[25],int first,int last){
int i, j, pivot, temp;
if(first<last){
pivot=first;
i=first;
j=last;
while(i<j){
while(number[i]<=number[pivot]&&i<last)
i++;
while(number[j]>number[pivot])
j--;
if(i<j){
temp=number[i];
number[i]=number[j];
number[j]=temp;
}
}
temp=number[pivot];
number[pivot]=number[j];
number[j]=temp;
quicksort(number,first,j-1);
quicksort(number,j+1,last);
}
}
int main(){
int i, count, number[25];
printf("How many elements are u going to enter?: ");
scanf("%d",&count);
printf("Enter %d elements: ", count);
for(i=0;i<count;i++)
scanf("%d",&number[i]);
quicksort(number,0,count-1);
printf("Order of Sorted elements: ");
for(i=0;i<count;i++)
printf(" %d",number[i]);
return 0;
}
Example 2: Quick sort in C
// Quick sort in C
#include <stdio.h>
// function to swap elements
void swap(int *a, int *b) {
int t = *a;
*a = *b;
*b = t;
}
// function to find the partition position
int partition(int array[], int low, int high) {
// select the rightmost element as pivot
int pivot = array[high];
// pointer for greater element
int i = (low - 1);
// traverse each element of the array
// compare them with the pivot
for (int j = low; j < high; j++) {
if (array[j] <= pivot) {
// if element smaller than pivot is found
// swap it with the greater element pointed by i
i++;
// swap element at i with element at j
swap(&array[i], &array[j]);
}
}
// swap the pivot element with the greater element at i
swap(&array[i + 1], &array[high]);
// return the partition point
return (i + 1);
}
void quickSort(int array[], int low, int high) {
if (low < high) {
// find the pivot element such that
// elements smaller than pivot are on left of pivot
// elements greater than pivot are on right of pivot
int pi = partition(array, low, high);
// recursive call on the left of pivot
quickSort(array, low, pi - 1);
// recursive call on the right of pivot
quickSort(array, pi + 1, high);
}
}
// function to print array elements
void printArray(int array[], int size) {
for (int i = 0; i < size; ++i) {
printf("%d ", array[i]);
}
printf("\n");
}
// main function
int main() {
int data[] = {8, 7, 2, 1, 0, 9, 6};
int n = sizeof(data) / sizeof(data[0]);
printf("Unsorted Array\n");
printArray(data, n);
// perform quicksort on data
quickSort(data, 0, n - 1);
printf("Sorted array in ascending order: \n");
printArray(data, n);
}
Example 3: quicksort in code
// A full c++ quicksort algorithm no bs
// quicksort in code
#include <iostream>
using namespace std;
void QuickSort(int arr[], int start, int end);
int Partition(int arr[], int start, int end);
void SwapArrMem(int arr[], int a, int b);
int main()
{
int arr[4]; //change the size of the array to your desired array size
cout << "enter " << sizeof(arr) / sizeof(arr[0]) << " numbers. press enter after input" << endl;
for (int i = 0; i < sizeof(arr) / sizeof(arr[0]); i++)
{
cin >> arr[i];
}
cout << endl << "The sorted numbers are:" << endl << endl;
QuickSort(arr, 0, sizeof(arr) / sizeof(arr[0]) - 1);
for (int i = 0; i < sizeof(arr) / sizeof(arr[0]); i++)
{
cout << arr[i] << endl;
}
}
void QuickSort(int arr[], int start, int end)
{
if (start >= end) return;
int index = Partition(arr, start, end);
QuickSort(arr, start, index - 1);
QuickSort(arr, index + 1, end);
}
int Partition(int arr[], int start, int end)
{
int pivotindex = start;
int pivotvalue = arr[end];
for (int i = start; i < end; i++)
{
if (arr[i] < pivotvalue)
{
SwapArrMem(arr, i, pivotindex);
pivotindex++;
}
}
SwapArrMem(arr, pivotindex, end);
return pivotindex;
}
void SwapArrMem(int arr[], int a, int b)
{
int temp = arr[a];
arr[a] = arr[b];
arr[b] = temp;
}
Example 4: quicksort in c
int cmpfunc (const void * a, const void * b) {
return ( *(int*)a - *(int*)b );
}