/*第一段，以-1 -1 -1 -1作为结束标志，一次输出所有结果*/
# include <stdio.h>
# define PHYSICAL	23
# define EMOTIONAL	28
# define INTELLECTUAL	33
# define BIG_CYCLE	21252
typedef struct caseNode
{
	int days;
	struct caseNode * next;
}CASE_NODE;

typedef struct
{
	CASE_NODE *head;
	CASE_NODE *rear;
}CASE;

CASE * CreateCase()
{
	CASE *c;
	c = malloc(sizeof(CASE));
	c->head = malloc(sizeof(CASE_NODE));
	c->rear = c->head;
	return c;
}

void AddCase(CASE * c, int days)
{
	CASE_NODE *cn;
	cn = malloc(sizeof(CASE_NODE));
	cn->days = days;
	cn->next = NULL;
	c->rear->next = cn;
	c->rear = cn;
}

void DeleteCase(CASE *c)
{
	CASE_NODE *cn, *p;
	cn = c->head;
	while(cn != c->rear)
	{
		p = cn;
		cn = cn->next;
		free(p);
	}
	free(cn);
	free(c);
}

void PrintCase(CASE *c)
{
	CASE_NODE *p;
	int i = 1;
	p = c->head->next;
	while(p != NULL)
	{
		printf("Case %d: the next triple peak occurs in %d days.\n", i, p->days);
		p = p->next;
		i++;
	}
}

int main()
{
	int p, e, i, d, x;
	CASE *c;
	c = CreateCase();
	for(;;)
	{
		scanf("%d%d%d%d", &p, &e, &i, &d);
		if(p < 0 || e < 0 || i < 0 || d < 0) break;
		p %= PHYSICAL;
		e %= EMOTIONAL;
		i %= INTELLECTUAL;
		x = i;
		while(!(((x-p)%PHYSICAL==0)&&((x-e)%EMOTIONAL==0)))
			x += INTELLECTUAL;
		x -= d;
		if(x <= 0) x += BIG_CYCLE;
		AddCase(c, x);
	}
	PrintCase(c);
	DeleteCase(c);
}

/*第二段，得到一组数据就计算并输出一次结果，以-1 -1 -1 -1为标志退出程序*/
# include <stdio.h>

# define PHYSICAL	23
# define EMOTIONAL	28
# define INTELLECTUAL	33
# define BIG_CYCLE	21252

int main()
{
	int p, e, i, d, x, index;
	index = 1;
	for(;;)
	{
		scanf("%d%d%d%d", &p, &e, &i, &d);
		if(p < 0 || e < 0 || i < 0 || d < 0) break;
		p %= PHYSICAL;
		e %= EMOTIONAL;
		i %= INTELLECTUAL;
		x = i;
		while(!(((x-p)%PHYSICAL==0)&&((x-e)%EMOTIONAL==0)))
			x += INTELLECTUAL;
		x -= d;
		if(x <= 0) x += BIG_CYCLE;
		printf("Case %d: the next triple peak occurs in %d days.\n", index, x);
		index++;
	}
	return 0;
}

哪位能解释一下为什么？