K&R的快速排序函数所需的参数是什么？

K&R的快速排序函数需要提供待排序数组的指针、数组第一个元素的下标和数组最后一个元素的下标作为参数。下面是一个示例代码：

#include <stdio.h>

void swap(int v[], int i, int j)
{
    int temp;

    temp = v[i];
    v[i] = v[j];
    v[j] = temp;
}

void qsort(int v[], int left, int right)
{
    int i, last;

    if (left >= right)   /* do nothing if array contains */
        return;         /* fewer than two elements */

    swap(v, left, (left + right)/2); /* move partition elem */
    last = left;                    /* to v[0] */
    for (i = left + 1; i <= right; i++)   /* partition */
        if (v[i] < v[left])
            swap(v, ++last, i);
    swap(v, left, last);            /* restore partition elem */
    qsort(v, left, last-1);
    qsort(v, last+1, right);
}

int main()
{
    int arr[] = { 3, 7, 2, 6, 4, 5, 8, 1 };
    int n = sizeof(arr) / sizeof(arr[0]);

    qsort(arr, 0, n - 1);

    for (int i = 0; i < n; i++)
        printf("%d ", arr[i]);

    return 0;
}