帮我用c语言写一个通讯录

好的，下面是一个简单的通讯录程序，可以添加、查找、删除联系人信息：

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

#define MAX_NAME_LEN 20
#define MAX_PHONE_LEN 11
#define MAX_CONTACTS 100

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

struct Contact contacts[MAX_CONTACTS];
int num_contacts = 0;

int add_contact() {
    if (num_contacts >= MAX_CONTACTS) {
        printf("Error: too many contacts\n");
        return 0;
    }
    struct Contact c;
    printf("Enter name: ");
    scanf("%s", c.name);
    printf("Enter phone: ");
    scanf("%s", c.phone);
    contacts[num_contacts++] = c;
    printf("Added contact: %s, %s\n", c.name, c.phone);
    return 1;
}

void find_contact() {
    char name[MAX_NAME_LEN];
    printf("Enter name to find: ");
    scanf("%s", name);
    for (int i = 0; i < num_contacts; i++) {
        if (strcmp(contacts[i].name, name) == 0) {
            printf("Found contact: %s, %s\n", contacts[i].name, contacts[i].phone);
            return;
        }
    }
    printf("Contact not found\n");
}

void delete_contact() {
    char name[MAX_NAME_LEN];
    printf("Enter name to delete: ");
    scanf("%s", name);
    for (int i = 0; i < num_contacts; i++) {
        if (strcmp(contacts[i].name, name) == 0) {
            for (int j = i; j < num_contacts-1; j++) {
                contacts[j] = contacts[j+1];
            }
            num_contacts--;
            printf("Deleted contact: %s, %s\n", name, contacts[i].phone);
            return;
        }
    }
    printf("Contact not found\n");
}

int main() {
    int choice;
    do {
        printf("\n1. Add contact\n");
        printf("2. Find contact\n");
        printf("3. Delete contact\n");
        printf("4. Quit\n");
        printf("Enter choice: ");
        scanf("%d", &choice);
        switch (choice) {
            case 1:
                add_contact();
                break;
            case 2:
                find_contact();
                break;
            case 3:
                delete_contact();
                break;
            case 4:
                printf("Goodbye!\n");
                break;
            default:
                printf("Invalid choice\n");
                break;
        }
    } while (choice != 4);
    return 0;
}

在这个程序中，我们使用了一个结构体Contact来表示联系人信息，使用一个静态数组contacts来存储所有联系人，使用一个变量num_contacts来记录当前有多少个联系人。程序提供了三个函数add_contact、find_contact和delete_contact来实现添加、查找和删除联系人信息。在主函数中，我们使用一个循环来不断读取用户的选择，直到用户选择退出程序。