Question

implement void Quick_Sort(int A[],int l,int r)

to sort array of integers in ascending order using the first element as a pivot, you can add any parameter you want

Note : you are only allowed to use java language

Answer 1

public class Main
{
//method for partition
public static int partition(int a[], int l, int h)
{
int pvt = a[l];
int i = l - 1;
int temp;
  
for (int j = l; j <= h - 1; j++)
{
if (a[j] < pvt)
{
i++;
  
//swapping
temp = a[i];
a[i] = a[j];
a[j] = temp;
}
}
temp = a[i + 1];
a[i + 1] = a[h];
a[h] = temp;
return i + 1;
}
  
//method for quick sort
public static void Quick_Sort(int A[], int l, int r)
{
if (l < r)
{
  
int p = partition(A, l, r);
Quick_Sort(A, l, p - 1);
Quick_Sort(A, p + 1, r);
}
}
   public static void main(String[] args)
   {
   //array declaration and initialization
int a[] = {20, 55, 11, 64, 97, 99, 74, 85, 34, 35, 74, 11, 47, 65, 69};
  
//method calling
Quick_Sort(a, 0, 14);
  
System.out.println("The array after sorting is: ");
for(int i=0; i<=14; i++)
{
System.out.print(a[i] + " ");
}
      
   }
}

OUTPUT:

The array after sorting is:
11 11 69 47 34 35 55 20 85 65 74 74 64 97 99