quick_sort_in_java.java

public class QuickSort {
    public static void main(String[] args) {
        int[] arr = {9, 7, 5, 11, 12, 2, 14, 3, 10, 6};
        quickSort(arr, 0, arr.length - 1);
        
        System.out.println("Sorted Array:");
        for (int num : arr) {
            System.out.print(num + " ");
        }
    }
    
    public static void quickSort(int[] arr, int low, int high) {
        if (low < high) {
            int pivotIndex = partition(arr, low, high);
            
            // Recursively sort the elements before and after the pivot
            quickSort(arr, low, pivotIndex - 1);
            quickSort(arr, pivotIndex + 1, high);
        }
    }
    
    public static int partition(int[] arr, int low, int high) {
        int pivot = arr[high]; // Choose the last element as the pivot
        int i = low - 1; // Index of smaller element
        
        for (int j = low; j < high; j++) {
            if (arr[j] < pivot) {
                i++;
                
                // Swap arr[i] and arr[j]
                int temp = arr[i];
                arr[i] = arr[j];
                arr[j] = temp;
            }
        }
        
        // Swap arr[i+1] and pivot (arr[high])
        int temp = arr[i + 1];
        arr[i + 1] = arr[high];
        arr[high] = temp;
        
        return i + 1;
    }
}