c语言 通讯录管理系统

好的，通讯录管理系统可以分为添加联系人、删除联系人、修改联系人、查询联系人和显示所有联系人等功能。下面是一个简单的 C 语言实现：

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

#define MAX_NAME_LEN 20
#define MAX_PHONE_LEN 15
#define MAX_CONTACTS_NUM 100

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

int contacts_num = 0;
Contact contacts[MAX_CONTACTS_NUM];

void add_contact() {
    if (contacts_num == MAX_CONTACTS_NUM) {
        printf("The contacts list is full.\n");
        return;
    }
    printf("Input name and phone number: ");
    scanf("%s%s", contacts[contacts_num].name, contacts[contacts_num].phone);
    contacts_num++;
    printf("Contact added successfully.\n");
}

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

void modify_contact() {
    char name[MAX_NAME_LEN];
    printf("Input name to modify: ");
    scanf("%s", name);
    int i;
    for (i = 0; i < contacts_num; i++) {
        if (strcmp(contacts[i].name, name) == 0) {
            printf("Input new phone number: ");
            scanf("%s", contacts[i].phone);
            printf("Contact modified successfully.\n");
            return;
        }
    }
    printf("Contact not found.\n");
}

void query_contact() {
    char name[MAX_NAME_LEN];
    printf("Input name to query: ");
    scanf("%s", name);
    int i;
    for (i = 0; i < contacts_num; i++) {
        if (strcmp(contacts[i].name, name) == 0) {
            printf("Name: %s\nPhone: %s\n", contacts[i].name, contacts[i].phone);
            return;
        }
    }
    printf("Contact not found.\n");
}

void display_contacts() {
    int i;
    for (i = 0; i < contacts_num; i++) {
        printf("Name: %s\nPhone: %s\n", contacts[i].name, contacts[i].phone);
    }
}

int main() {
    while (1) {
        printf("Select an operation:\n");
        printf("1. Add contact\n");
        printf("2. Delete contact\n");
        printf("3. Modify contact\n");
        printf("4. Query contact\n");
        printf("5. Display all contacts\n");
        printf("6. Exit\n");
        int choice;
        scanf("%d", &choice);
        switch (choice) {
            case 1:
                add_contact();
                break;
            case 2:
                delete_contact();
                break;
            case 3:
                modify_contact();
                break;
            case 4:
                query_contact();
                break;
            case 5:
                display_contacts();
                break;
            case 6:
                printf("Goodbye!\n");
                return 0;
            default:
                printf("Invalid choice.\n");
                break;
        }
    }
}

这里使用了结构体来表示联系人信息，同时使用了动态数组来存储联系人列表。注意在添加联系人时要检查列表是否已满，删除联系人和修改联系人时要先查询联系人是否存在。