用C++帮我写一个程序，要求用client-server实现多个用户的群组交流

好的，以下是一个简单的示例程序，实现了用 client-server 架构实现多个用户的群组交流：

1. 服务器端：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>

#define PORT 8888
#define MAX_CLIENTS 10
#define BUFFER_SIZE 1024

int main() {
    int server_fd, client_fds[MAX_CLIENTS], max_fd, activity, i, valread, sd;
    struct sockaddr_in address;
    char buffer[BUFFER_SIZE];
    fd_set readfds;

    // 初始化客户端文件描述符数组
    for (i = 0; i < MAX_CLIENTS; i++) {
        client_fds[i] = 0;
    }

    // 创建服务器套接字
    if ((server_fd = socket(AF_INET, SOCK_STREAM, 0)) == 0) {
        perror("socket failed");
        exit(EXIT_FAILURE);
    }

    // 设置服务器套接字属性
    if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &(int){1}, sizeof(int)) < 0) {
        perror("setsockopt failed");
        exit(EXIT_FAILURE);
    }

    // 绑定服务器套接字到指定端口
    address.sin_family = AF_INET;
    address.sin_addr.s_addr = INADDR_ANY;
    address.sin_port = htons(PORT);
    if (bind(server_fd, (struct sockaddr *)&address, sizeof(address)) < 0) {
        perror("bind failed");
        exit(EXIT_FAILURE);
    }

    // 监听连接请求
    if (listen(server_fd, MAX_CLIENTS) < 0) {
        perror("listen failed");
        exit(EXIT_FAILURE);
    }

    printf("Server is listening on port %d...\n", PORT);

    // 等待连接请求并处理
    while (1) {
        // 将所有客户端文件描述符添加到 readfds 集合中
        FD_ZERO(&readfds);
        FD_SET(server_fd, &readfds);
        max_fd = server_fd;
        for (i = 0; i < MAX_CLIENTS; i++) {
            sd = client_fds[i];
            if (sd > 0) {
                FD_SET(sd, &readfds);
            }
            if (sd > max_fd) {
                max_fd = sd;
            }
        }

        // 等待 I/O 事件发生
        activity = select(max_fd + 1, &readfds, NULL, NULL, NULL);
        if (activity < 0) {
            perror("select failed");
            exit(EXIT_FAILURE);
        }

        // 处理连接请求
        if (FD_ISSET(server_fd, &readfds)) {
            int new_socket;
            struct sockaddr_in client_address;
            socklen_t client_size = sizeof(client_address);

            if ((new_socket = accept(server_fd, (struct sockaddr *)&client_address, &client_size)) < 0) {
                perror("accept failed");
                exit(EXIT_FAILURE);
            }

            printf("New connection from %s:%d\n", inet_ntoa(client_address.sin_addr), ntohs(client_address.sin_port));

            // 将新创建的套接字添加到客户端文件描述符数组中
            for (i = 0; i < MAX_CLIENTS; i++) {
                if (client_fds[i] == 0) {
                    client_fds[i] = new_socket;
                    break;
                }
            }
        }

        // 处理客户端消息
        for (i = 0; i < MAX_CLIENTS; i++) {
            sd = client_fds[i];
            if (FD_ISSET(sd, &readfds)) {
                if ((valread = read(sd, buffer, BUFFER_SIZE)) == 0) {
                    // 客户端断开连接
                    printf("Client disconnected\n");
                    close(sd);
                    client_fds[i] = 0;
                } else {
                    // 广播消息给所有客户端
                    for (i = 0; i < MAX_CLIENTS; i++) {
                        if (client_fds[i] != 0 && client_fds[i] != sd) {
                            send(client_fds[i], buffer, valread, 0);
                        }
                    }
                }
            }
        }
    }

    return 0;
}

2. 客户端：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>

#define SERVER_ADDRESS "127.0.0.1"
#define PORT 8888
#define BUFFER_SIZE 1024

int main() {
    int sockfd;
    struct sockaddr_in server_address;
    char buffer[BUFFER_SIZE];

    // 创建客户端套接字
    if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
        perror("socket failed");
        exit(EXIT_FAILURE);
    }

    // 设置服务器地址和端口
    server_address.sin_family = AF_INET;
    server_address.sin_port = htons(PORT);
    if (inet_pton(AF_INET, SERVER_ADDRESS, &server_address.sin_addr) <= 0) {
        perror("inet_pton failed");
        exit(EXIT_FAILURE);
    }

    // 连接服务器
    if (connect(sockfd, (struct sockaddr *)&server_address, sizeof(server_address)) < 0) {
        perror("connect failed");
        exit(EXIT_FAILURE);
    }

    printf("Connected to server\n");

    // 发送消息给服务器
    while (1) {
        printf("> ");
        fgets(buffer, BUFFER_SIZE, stdin);
        send(sockfd, buffer, strlen(buffer), 0);
    }

    return 0;
}

以上是一个简单的示例程序，仅供参考。实际应用中，还需要考虑如何处理异常情况，如连接断开、客户端超时等。