单向链表实例：终端交互简易通讯录

#include    <stdio.h>
#include    <stdlib.h>
#include    <string.h>


typedef struct Contacts_infomation{
    char name[13];
    char work_unit[61];
    char phone_number[12];
    char E_mail[61];
    struct Contacts_infomation *next;
}con_info;


con_info * Creat_node(void)
{
    con_info *new;

    new = (con_info *)malloc(sizeof(con_info));
    if(!new){
        printf("Malloc Error!
");
        exit(-1);
    }    
    new->next = NULL;
    
    return new;
}

int insert_node(con_info ** phead)
{
    con_info *new, *cur;    

    cur = *phead;
    new = Creat_node();
    if(!new){
        return -1;
    }    
    
    printf("please input name,work unit,phone number and E-mail (separated by enter):
");
    printf("name:");
    scanf("%s", new->name);
    printf("work unit:");
    scanf("%s", new->work_unit);
    printf("phone number:");
    scanf("%s", new->phone_number);
    printf("E-mail:");
    scanf("%s", new->E_mail);
    
    if(!(*phead)){
        *phead = new;
        return 0;
    }
    if(strncmp((*phead)->name,new->name,3) > 0){
        new->next = *phead;
        *phead = new;
        return 0;
    }
    while(cur->next){
        if(strncmp(cur->next->name, new->name,3) > 0){
            new->next = cur->next;
            cur->next = new;
            return 0;
        }
    }
    cur->next = new;

    return 0;
}
int  del_node(con_info **phead){
    con_info *cur = *phead;
    char name[13];

    if(!cur){
        printf("Address book is empty
");
        return -1;
    }
    printf("please input want delete name: ");
    scanf("%s", name);

    if(strcasecmp((*phead)->name, name) == 0){
        con_info *tmp = (*phead)->next;
        free(*phead);
        *phead = tmp;
        return 0;
    }
    while(cur->next){
        if(strcmp(cur->next->name, name) == 0){
            con_info *tmp = cur->next;
            cur->next = tmp->next;
            free(tmp);
            return 0;
        }
        cur = cur->next;
    }
    getchar();
    printf("

Can't find %s
", name);
    printf("

Please input Enter continue...");
    char ch = getchar();

    return 0;    
}

int mod_node(con_info **phead){
    con_info *cur =  *phead;
    char name[13];
    char reply[10];

    if(!cur){
        printf("Address book is empty
");
        return -1;
    }
    printf("Please input want modify name: ");
    scanf("%s", name);
    while(cur){
        if(strcasecmp(cur->name, name) == 0){

            printf("Modify name?(y/any key): ");
            scanf("%s", reply);
            if(strcmp(reply, "y") == 0){
                printf("Please new input name: ");            
                scanf("%s", cur->name);
            }
            printf("Modify work unit?(y/any key): ");
            scanf("%s", reply);
            if(strcmp(reply, "y") == 0){
                printf("Please input new work_unit: ");
                scanf("%s", cur->work_unit);
            }
            printf("Modify phone number?(y/any key): ");
            scanf("%s", reply);
            if(strcmp(reply, "y") == 0){
                printf("Please input new phone number: ");
                scanf("%s", cur->phone_number);
            }
            printf("Modify E-mail?(y/any key): ");
            scanf("%s", reply);
            if(strcmp(reply, "y") == 0){
                printf("Please input new E-mail: ");
                scanf("%s", cur->E_mail);
            }
            return 0;
        }
    cur = cur->next;
    }
    getchar();
    printf("No contact was found.
");
    printf("

Please input Enter continue...");
    char ch = getchar();
    return 0;
}

int search_node(con_info **phead){
    con_info *cur = *phead;
    char in[13];
    if(!cur){
        printf("Address book is empty
");
        return -1;
    }
    printf("Please input name or phone number: ");
    scanf("%s", in);

    while(cur){
        if(strcasecmp(cur->name, in) == 0 || strcmp(cur->phone_number, in) == 0){
            printf("name		work unit							phone number		E-mail
");
            printf("%-16s%-64s%-24s%-30s
", cur->name, cur->work_unit, cur->phone_number, cur->E_mail);
            getchar();
            printf("Please input Enter continue...");
            char ch = getchar();

            return 0;
        }
        cur = cur->next;
    }
    printf("

Can't find %s
", in);
    getchar();
    printf("Please input Enter continue...");
    char ch = getchar();
    
    return 0;
}
int print_con(con_info *phead){
    con_info *cur = phead;
    
    printf("name		work unit							phone number		E-mail
");
    if(!cur){
        printf("NULL
");
        return -1;
    }
    while(cur){
        printf("%-16s%-64s%-24s%-30s
", cur->name, cur->work_unit, cur->phone_number, cur->E_mail);
        cur = cur->next;
    }
    getchar();
    printf("

Please input Enter continue...");
    char ch = getchar();

    return 0;
}




int main(void)
{
    con_info *head = NULL;
    char op[20];
    char dd[20];

    do{
        printf("


1.New contacts
2.Delete contact
3.Unfoling contacts
4.Modify contacts
5.serch
6.Exit

8.Clean screen

********************************


");
        printf("Please inpu op: ");
        scanf("%s", op);
        printf("

");
        if(!strcmp(op,"1")){    
            insert_node(&head);
        }else if(!strcmp(op, "2")){
            del_node(&head);
        }else if(!strcmp(op, "3")){
            print_con(head);
        }else if(!strcmp(op, "4")){
            mod_node(&head);
        }else if(!strcmp(op, "5")){
            search_node(&head);
        }else if(!strcmp(op, "6")){
            break;
        }else if(!strcmp(op, "8")){
            //printf("33[2J") ;
            system("clear");
        }
        else{
            printf("Ipunt opearton error
");
        }
    }while(1);        
        
    return 0;
}

由于通讯录不怎么需要倒序操作，又是一个简易的，所以干脆就使用了单向链表。Running demo:

交互界面（^_^简易的，所以特别简陋）：

各个功能演示一遍：