帮助实施快速排序

本文介绍了帮助实施快速排序的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

这是我所拥有的，它不起作用.无法弄清原因...问题可能出在quick_sort函数中.

This is what I have and it doesn't work. Can't figure out why... The problem is probably in the quick_sort function.

#include <stdio.h> #include <stdlib.h> void quick_sort(int * a, int l, int r); void swap(int * a, int i, int j); int main(void) { #define N 10 int a[N], i; for (i = 0; i < N; ++i) { a[i] = rand(); printf("%d\n", a[i]); } quick_sort(a, 0, N - 1); for (i = 0; i < N; ++i) printf("%d\n", a[i]); return 0; #undef N } void quick_sort(int * a, int l, int r) { int i, j; if (l < r) { swap(a, rand() % (r - l + 1), r); i = l; for (j = l; j < r; ++j) if (a[j] < a[r]) { swap(a, i, j); ++i; } swap(a, i, r); quick_sort(a, l, i - 1); quick_sort(a, i + 1, r); } } void swap(int * a, int i, int j) { int k; k = a[i]; a[i] = a[j]; a[j] = k; }

推荐答案

修复此行:swap(a, rand() % (r - l + 1), r);

应该是:swap(a, l + rand() % (r - l + 1), r);