用c语言写一个通讯录

下面是用 C 语言实现通讯录的示例代码：

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

#define MAX_NAME_LEN 50
#define MAX_PHONE_LEN 20

typedef struct {
    char name[MAX_NAME_LEN];
    char phone[MAX_PHONE_LEN];
} Contact;

typedef struct {
    Contact *contacts;
    int size;
    int capacity;
} AddressBook;

AddressBook *create_address_book(int capacity) {
    AddressBook *book = (AddressBook *)malloc(sizeof(AddressBook));
    book->contacts = (Contact *)malloc(capacity * sizeof(Contact));
    book->size = 0;
    book->capacity = capacity;
    return book;
}

void destroy_address_book(AddressBook *book) {
    free(book->contacts);
    free(book);
}

void add_contact(AddressBook *book, Contact *contact) {
    if (book->size >= book->capacity) {
        book->capacity *= 2;
        book->contacts = (Contact *)realloc(book->contacts, book->capacity * sizeof(Contact));
    }
    book->contacts[book->size++] = *contact;
    printf("Contact added successfully.\n");
}

void print_contact(Contact *contact) {
    printf("%s: %s\n", contact->name, contact->phone);
}

void print_address_book(AddressBook *book) {
    printf("Address Book:\n");
    for (int i = 0; i < book->size; i++) {
        print_contact(&book->contacts[i]);
    }
}

int main() {
    AddressBook *book = create_address_book(10);
    Contact contact;

    while (1) {
        printf("Enter name (or 'quit' to exit): ");
        scanf("%s", contact.name);
        if (strcmp(contact.name, "quit") == 0) {
            break;
        }

        printf("Enter phone number: ");
        scanf("%s", contact.phone);

        add_contact(book, &contact);
    }

    print_address_book(book);
    destroy_address_book(book);

    return 0;
}

这个通讯录程序使用一个结构体 `Contact` 存储每个联系人的姓名和电话号码，使用另一个结构体 `AddressBook` 存储所有联系人。`create_address_book()` 函数用于创建一个新的通讯录，`add_contact()` 函数用于添加一个联系人，`print_address_book()` 函数用于打印整个通讯录，`destroy_address_book()` 函数用于销毁通讯录并释放内存。在 `main()` 函数中，我们可以通过循环来不断添加联系人，输入 `quit` 结束输入。