www.pudn.com > gc.rar > 8_4.C

# include  
# include  
typedef struct {               // 顾客信息结构 
	int arrive; 
	int treat; 
}NODE; 
 
typedef struct node { 
	NODE data; 
	struct node *link; 
}LNODE; 
 
LNODE *head,*tail; 
 
NODE curr,temp; 
 
char Fname[120]; 
FILE *fp;           //指向FILE类型结构体的指针变量 
 
/*函数,链接队列进队函数*/ 
void len_queue(LNODE **hpt,LNODE **tpt,NODE x) 
{ 
	LNODE *p = (LNODE *)malloc(sizeof(LNODE)); 
	p->data = x; 
	p->link = NULL; 
	if (*hpt == NULL) *tpt = *hpt = p; 
	else 
		*tpt = (*tpt)->link = p; 
} 
 
/*函数,链接队列出队函数*/ 
int lde_queue(LNODE **hpt,LNODE **tpt,NODE *cp) 
{ 
	LNODE *p = *hpt; 
	if (*hpt == NULL) return 1 ;               //对空 
	*cp = (*hpt)->data; 
	*hpt = (*hpt)->link; 
	if (*hpt == NULL) *tpt = NULL; 
	free(p); 
	return 0; 
} 
 
 
void main() 
{ 
	int dwait = 0,         //接待员总等待时间 
	clock = 0, 
	wait = 0,              //顾客总等待时间 
	count = 0,             //顾客总人数 
	have = 0,finish; 
	printf("Enter file name."); 
	printf("输入同目录下wait.txt的完整物理路径\n"); 
	scanf("%s",Fname); 
	if ((fp = fopen(Fname,"r")) == NULL) {            //打开文件 
		printf("Can't open file %s",Fname); 
		return; 
	} 
	head = NULL; tail=NULL; 
	have = fscanf(fp,"%d%d",&temp.arrive, &temp.treat);   /*正确读入,have为2*/ 
	do {   /*约定每轮循环,接待一位顾客*/ 
		if (head == NULL && have == 2) {    /*等待队列为空,但还有顾客*/ 
			dwait += temp.arrive - clock;   /*累计接待员总等待时间  */ 
			clock = temp.arrive;            /*时钟推进到暂存顾客的到达时间*/ 
			len_queue(&head,&tail,temp);    /*暂存变量中的顾客信息进队*/ 
			have = fscanf(fp,"%d%d",&temp.arrive,&temp.treat); /*fp,文件指针,从磁盘文件上读入*/ 
		} 
		count ++;                      /*累计顾客人数*/ 
		lde_queue(&head,&tail,&curr);  /*出队一个顾客信息*/ 
		wait += clock - curr.arrive;      /*累计顾客的总等待时间*/ 
		finish = clock + curr.treat;       /*设定接待结束时间*/ 
		while (have == 2 && temp.arrive <= finish) { 
			/*下一位顾客的到达时间在当前顾客接待结束之前*/ 
			len_queue(&head,&tail,temp);       /*暂存变量中的顾客信息进队*/ 
			have = fscanf(fp,"%d%d",&temp.arrive,&temp.treat); 
		} 
		clock = finish;          /*时钟推进到当前顾客接待结束时间 */ 
	} while(have == 2 || head!=NULL); 
	printf("结果:接待员等待时间%d\n顾客平均等待时间%f\n",dwait,(double)wait/count); 
	printf("模拟总时间:%d,顾客人数:%d,总等待时间:%d\n",clock,count,wait); 
}