Java Quicksort Partition Error

Question

Consider the following implementation of the Quicksort algorithm.

```java
public class Sorter {
    public static void quickSort(int[] arr, int low, int high) {
        if(low >= high) return;
        int pivotIndex = partition(arr, low, high);
        quickSort(arr, low, pivotIndex - 1);
        quickSort(arr, pivotIndex + 1, high);
    }
    public static int partition(int[] arr, int low, int high) {
        int pivot = arr[high];
        int i = low;
        for(int j = low; j <= high; j++) {
            if(arr[j] < pivot) {
                int temp = arr[i];
                arr[i] = arr[j];
                arr[j] = temp;
                i++;
            }
        }
        int temp = arr[i];
        arr[i] = arr[high];
        arr[high] = temp;
        return i;
    }
}
```

Which statement best describes a logical error in the provided code?

Accepted Answer

The for-loop in the partition method should use 'j < high' instead of 'j <= high' to avoid comparing the pivot with itself.

Answer

The condition 'low >= high' in quickSort is incorrect and should instead be 'low > high'.

Answer

The recursive calls in quickSort include incorrect indices that cause elements to be skipped.

Answer

The pivot should always be chosen as the first element of the array rather than the last element.

Question Leaderboard