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Write a Java Program to Implement Quick Sort Algorithm
PROGRAM: Java Program to Implement Quick Sort Algorithm
/*Java Program to Implement Quick Sort Algorithm*/
import java.util.Arrays;
class Quicksort {
// method to find the partition position
static int partition(int array[], int low, int high) {
// choose the rightmost element as pivot
int pivot = array[high];
// pointer for greater element
int i = (low – 1);
// traverse through all elements
// compare each element with 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++;
// swapping element at i with element at j
int temp = array[i];
array[i] = array[j];
array[j] = temp;
}
}
// swap the pivot element with the greater element specified by i
int temp = array[i + 1];
array[i + 1] = array[high];
array[high] = temp;
// return the position from where partition is done
return (i + 1);
}
static void quickSort(int array[], int low, int high) {
if (low < high) {
// find pivot element such that
// elements smaller than pivot are on the left
// elements greater than pivot are on the right
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);
}
}
public static void main(String args[]) {
int[] data = { 8, 7, 2, 1, 0, 9, 6 };
System.out.println(“Unsorted Array”);
System.out.println(Arrays.toString(data));
int size = data.length;
// call quicksort() on array data
quickSort(data, 0, size – 1);
System.out.println(“Sorted Array in Ascending Order “);
System.out.println(Arrays.toString(data));
}
}
