例1-6 通信录.c

王为青 刘变红 编著《C语言高级编程及实例剖析》源代码

/* Note:Your choice is C IDE */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct addr
{
	char name[30];
	char street[40];
	char city[20];
	char state[3];
	char tel[11];
	struct addr *next;  /* pointer to next entry */
 }record;
struct addr *head,*start;
struct addr *last;
int menu_select();
void enter();
void deleted();
void search();
void main()
{
	char s[80],choice;
	struct addr *info;
	start=last=NULL;

		switch(menu_select())
	{
	case 1:enter();
		break;
	case 2:deleted();
		break;
	case 3:search();
		break;
	case 4:exit(0);
	}
}

int menu_select()
{
	char s[80];
	int c;
	printf("1__Enter a name\n");
	printf("2__Delete a record\n");
	printf("3__Search\n");
	printf("4__Quit\n");
	do
	{
		printf("\n Enter  your choice:");
		gets(s);
		c=atoi(s);
	}while(c<1||c>4);
	return(c);
}

struct addr* des_store(struct addr *i,struct addr *top)
{
	if(!last)
	{
		last=i;
		return(i);
	}
	else
	{
		top->next=i;
    	i->next=NULL;
	    last=i;
		return(i);
	}
}
void enter()
{
	struct addr *info;
	void inputs(char *,char *,int );
	int n;
	for(n=0;n<2;n++)
	{
		info=(struct addr *)malloc(sizeof(record));
		if(info==NULL)
		{ 
			printf("\n out of memory");
			return;
		}
        inputs("enter name:",info->name,30);
		if(info->name[0]=='0')
			break;
		else
		{
		    inputs("enter street:",info->street,40);
		    inputs("enter city:",info->city,20);
		    inputs("enter state:",info->state,3);
		    inputs("enter tel:",info->tel ,11);
		    start=des_store(info,start);
	  	    if(n==0)
		    	head=start;
		}
	}
}
	
void inputs(char *p1,char* s,int count)
{
	char p[40];
	do
	{
		printf("%s",p1);
		gets(p);
		if (strlen(p)>count)
			printf("\n too long\n");
	}while(strlen(p)>count);
	strcpy(s,p);
}

void display(struct addr *info)
{
	printf("%s\n",info->name);
	printf("%s\n",info->street);
	printf("%s\n",info->city);
	printf("%s\n",info->tel);
	printf("\n\n");
}

struct addr *find(char *name)
{
	struct addr *info;
	info=head;
	while(info)
	{
		if(!strcmp(name,info->name))
			return(info);
		else
			info=info->next;
	}
	return(info);
}

void search()
{
	char name[40];
	struct addr *info;
	printf("enter name to find:");
	gets(name);
	if((info=find(name))==NULL)
		printf("not found\n");
	else
		display(info);
}

void deleted()
{
	char s[80];
	struct addr*p1,*p2,*info;
	printf("enter name:");
	gets(s);
	info=find(s);
	if(info!=NULL)
	{
		if (head==info)
		{
			head=info->next;
			printf("deleted:%s\n",info->name);
			free(info);
		}
		else
		{
			p1=head->next;
			while(info!=p1)
			{
				p2=p1;
				p1=p1->next;
			}
			p2->next=p1->next;
			printf("deleted:%s\n",info->name);
			free(info);
		}
	}
	else
		printf("%s not find!\n",info->name);
}