queue3.c

来自「自己做的常用库和实现的数据结构。public domain.」· C语言 代码 · 共 50 行

/* Demo of simple loop queue, using array.
 *
 * Written by Cyril Hu ([e-mail]), public domain.
 */
#include "my.h"
#define MAX 13

struct qnode {
	int elem;
} a[MAX];

void en_queue(struct qnode *a, int e, size_t max) 
{
	static size_t i = 0;
	i %= max;
	struct qnode *rear = a + i++;
	rear->elem = e;
}

void de_queue(struct qnode *a, int *e, size_t max)
{
	static size_t i = 0;
	i %= max;
	struct qnode *front = a + i++;
	*e = front->elem;
}

int main(void)
{
	int i,b[MAX];
	for(i=0; i<(int)(MAX*0.8); i++)
		en_queue(a, i, MAX);
	puts("");
	for(i=0; i<(int)(MAX*0.8); i++)
		printf("%2d ", a[i].elem);

	for(i=0; i<(int)(MAX*0.5); i++)
		de_queue(a, &b[i], MAX);
	puts("");
	for(i=0; i<MAX; i++)
		printf("%2d ", b[i]);

	for(i=(int)(MAX * 0.8); i<(int)(MAX*0.8) + (int)(MAX*0.5); i++)
		en_queue(a, i, MAX);
	puts("");
	for(i=0; i<MAX; i++)
		printf("%2d ", a[i].elem);
	return 0;
}