【华为OD机试B卷】服务器广播、需要广播的服务器数量（C++/Java/Python）

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admin 1周前 (09-13) 阅读数 51 #Python

文章标签 Python

华为OD机试B卷：服务器广播问题

在华为OD机试B卷中，涉及到了服务器广播的问题。广播是一种网络通信对策，它允许一台服务器向网络中的所有其他服务器发送信息。本文将简要介绍怎样实现服务器广播，并给出需要广播的服务器数量的计算方法。以下将分别使用C++、Java和Python三种编程语言进行说明。

1. C++实现

C++在网络编程中，可以使用套接字（Socket）实现广播。以下是C++实现广播的明了示例：


#include <iostream>
#include <Winsock2.h>
#pragma comment(lib, "ws2_32.lib")
int main() {
    WSADATA wsaData;
    WSAStartup(MAKEWORD(2, 2), &wsaData);
    SOCKET sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    sockaddr_in addr;
    addr.sin_family = AF_INET;
    addr.sin_addr.S_un.S_addr = INADDR_ANY;
    addr.sin_port = htons(12345);
    bind(sock, (sockaddr*)&addr, sizeof(addr));
    int broadcast = 1;
    setsockopt(sock, SOL_SOCKET, SO_BROADCAST, (char*)&broadcast, sizeof(broadcast));
    sockaddr_in broadcastAddr;
    broadcastAddr.sin_family = AF_INET;
    broadcastAddr.sin_addr.S_un.S_addr = INADDR_BROADCAST;
    broadcastAddr.sin_port = htons(12345);
    const char* msg = "Hello, broadcast!";
    sendto(sock, msg, strlen(msg), 0, (sockaddr*)&broadcastAddr, sizeof(broadcastAddr));
    closesocket(sock);
    WSACleanup();
    return 0;
}

2. Java实现

在Java中，可以使用DatagramSocket和DatagramPacket实现广播。以下是Java实现广播的明了示例：


import java.net.*;
public class BroadcastServer {
    public static void main(String[] args) throws Exception {
        DatagramSocket socket = new DatagramSocket();
        InetAddress address = InetAddress.getByName("255.255.255.255");
        int port = 12345;
        String message = "Hello, broadcast!";
        byte[] buffer = message.getBytes();
        DatagramPacket packet = new DatagramPacket(buffer, buffer.length, address, port);
        socket.send(packet);
        socket.close();
    }
}

3. Python实现

Python中，可以使用socket库实现广播。以下是Python实现广播的明了示例：


import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
server_address = ('255.255.255.255', 12345)
message = 'Hello, broadcast!'
sock.sendto(message.encode(), server_address)
sock.close()