Quick Sort Algorithm

//Quick Sort Algorithm
import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        int[] array = new int[N];
        for (int i = 0; i < N; i++)
            array[i] = sc.nextInt();
        quickSort(array, 0, N - 1);
        System.out.println("Sorted Elements: ");
        for (int i = 0; i < N; i++) {
            System.out.print(array[i] + " ");
        }
        System.out.println();
    }

    public static int partition(int[] array, int p, int q) {
        int v = array[p];
        int i = p, j = q + 1;
        do {
            do {
                i++;
            } while (i < q && array[i] < v);
            do {
                j--;
            } while (j > p && array[j] > v);
            if (i < j) {
                interchange(array, i, j);
            }
        } while (i < j);
        interchange(array, p, j);
        return j;
    }

    public static void quickSort(int[] array, int p, int q) {
        if (p < q) {
            int j = partition(array, p, q);
            quickSort(array, p, j - 1);
            quickSort(array, j + 1, q);
        }
    }

    public static void interchange(int[] array, int i, int j) {
        int temp = array[i];
        array[i] = array[j];
        array[j] = temp;
    }
}

/*
Sample Test Case:

Input:
5
12 4 7 9 2

Output:
Sorted Elements:
2 4 7 9 12
*/