该楼层疑似违规已被系统折叠 隐藏此楼查看此楼

return不可能返回数组，于是子hanshu1quicksort最后没有用return，但是没有return又怎么可以更改a[N]？主函数中的quicksort(a, 0, N - 1);将a[N]复制后传递给形参a，quicksort(a, 0, N - 1);应该是只对a[N]的副本进行排序，最后输出的顺序应该和输入的一样，相当于没有排，但是结果却是排了，这是怎样实现的？和理论不是矛盾吗？

/*********************************************************

* From C PROGRAMMING: A MODERN APPROACH, Second Edition *

* By K. N. King *

* Copyright (c) 2008, 1996 W. W. Norton & Company, Inc. *

* All rights reserved. *

* This program may be freely distributed for class use, *

* provided that this copyright notice is retained. *

*********************************************************/

/* qsort.c (Chapter 9, page 207) */

/* Sorts an array of integers using Quicksort algorithm */

#include

#define N 10

void quicksort(int a[], int low, int high);

int split(int a[], int low, int high);

int main(void)

{

int a[N], i;

printf("Enter %d numbers to be sorted: ", N);

for (i = 0; i < N; i++)

scanf("%d", &a[i]);

quicksort(a, 0, N - 1);

printf("In sorted order: ");

for (i = 0; i < N; i++)

printf("%d ", a[i]);

printf("\n");

return 0;

}

void quicksort(int a[], int low, int high)

{

int middle;

if (low >= high) return;

middle = split(a, low, high);

quicksort(a, low, middle - 1);

quicksort(a, middle + 1, high);

}

int split(int a[], int low, int high)

{

int part_element = a[low];

for (;;) {

while (low < high && part_element <= a[high])

high--;

if (low >= high) break;

a[low++] = a[high];

while (low < high && a[low] <= part_element)

low++;

if (low >= high) break;

a[high--] = a[low];

}

a[high] = part_element;

return high;

}