68 lines
1.4 KiB
C
68 lines
1.4 KiB
C
|
/*
|
||
|
|
* C Program to Implement Quick Sort Using Randomization
|
||
|
|
*/
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#define MAX 100
|
||
|
|
void random_shuffle(int arr[])
|
||
|
|
{
|
||
|
|
srand(time(NULL));
|
||
|
|
int i, j, temp;
|
||
|
|
for (i = MAX - 1; i > 0; i--)
|
||
|
|
{
|
||
|
|
j = rand()%(i + 1);
|
||
|
|
temp = arr[i];
|
||
|
|
arr[i] = arr[j];
|
||
|
|
arr[j] = temp;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void swap(int *a, int *b)
|
||
|
|
{
|
||
|
|
int temp;
|
||
|
|
temp = *a;
|
||
|
|
*a = *b;
|
||
|
|
*b = temp;
|
||
|
|
}
|
||
|
|
int partion(int arr[], int p, int r)
|
||
|
|
{
|
||
|
|
int pivotIndex = p + rand()%(r - p + 1); //generates a random number as a pivot
|
||
|
|
int pivot;
|
||
|
|
int i = p - 1;
|
||
|
|
int j;
|
||
|
|
pivot = arr[pivotIndex];
|
||
|
|
swap(&arr[pivotIndex], &arr[r]);
|
||
|
|
for (j = p; j < r; j++)
|
||
|
|
{
|
||
|
|
if (arr[j] < pivot)
|
||
|
|
{
|
||
|
|
i++;
|
||
|
|
swap(&arr[i], &arr[j]);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
swap(&arr[i+1], &arr[r]);
|
||
|
|
return i + 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
void quick_sort(int arr[], int p, int q)
|
||
|
|
{
|
||
|
|
int j;
|
||
|
|
if (p < q)
|
||
|
|
{
|
||
|
|
j = partion(arr, p, q);
|
||
|
|
quick_sort(arr, p, j-1);
|
||
|
|
quick_sort(arr, j+1, q);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
int main()
|
||
|
|
{
|
||
|
|
int i;
|
||
|
|
int arr[MAX];
|
||
|
|
for (i = 0; i < MAX; i++)
|
||
|
|
arr[i] = i;
|
||
|
|
random_shuffle(arr); //To randomize the array
|
||
|
|
quick_sort(arr, 0, MAX-1); //function to sort the elements of array
|
||
|
|
for (i = 0; i < MAX; i++)
|
||
|
|
printf("%d \n", arr[i]);
|
||
|
|
return 0;
|
||
|
|
}
|