#include<iostream> #include<string> using namespace std; void str_any(string, string); int main() { string str1, str2; cin >> str1; cin >> str2; str_any(str1, str2); return 0; } void str_any(string s, string t) { int i, j, found = 0; for (i = 0; s[i] != '\0' && !found; i++) for (j = 0; t[j] != '\0' && !found; j++) if (s[i] == t[j]) { cout << "yes" << endl; found = 1; } if (!found) } cout << "no" << endl;每一行都是什么意思
时间: 2024-04-28 15:26:27 浏览: 53
这段代码是一个简单的字符串匹配程序,包括两个函数:main和str_any。
第1行包含两个头文件iostream和string。
第3行使用命名空间std。
第5-10行定义了名为str_any的函数,该函数接受两个字符串作为参数,用于在第一个字符串中查找是否有任何一个字符与第二个字符串中的字符匹配。
第12-16行定义了主函数main,它要求用户输入两个字符串,然后调用str_any函数进行字符串匹配。
第18-23行定义了str_any函数的实现。在嵌套的循环中,它比较第一个字符串中的每个字符是否与第二个字符串中的任何一个字符匹配。如果找到匹配,则输出“yes”,并将found置为1,表示找到了匹配。如果没有找到匹配,则输出“no”。
相关问题
C++使用多线程技术实现多客户端并发访问指定服务器Linux 客户端和服务端代码
客户端代码:
```c++
#include <iostream>
#include <string>
#include <thread>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netinet/in.h>
using namespace std;
void connect_server(int s)
{
struct sockaddr_in server_addr;
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(8888);
server_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
while (connect(s, (struct sockaddr*)&server_addr, sizeof(server_addr)) == -1)
{
cout << "连接服务器失败!" << endl;
sleep(1);
}
cout << "连接服务器成功!" << endl;
while (true)
{
string send_buf;
cout << "请输入要发送的内容:";
getline(cin, send_buf);
if (send_buf == "exit")
{
break;
}
send(s, send_buf.c_str(), send_buf.size(), 0);
char recv_buf[1024] = {0};
recv(s, recv_buf, sizeof(recv_buf), 0);
cout << "服务器返回:" << recv_buf << endl;
}
close(s);
}
int main()
{
int s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
thread t(connect_server, s);
t.join();
return 0;
}
```
服务端代码:
```c++
#include <iostream>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netinet/in.h>
using namespace std;
int main()
{
int s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
struct sockaddr_in server_addr;
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(8888);
server_addr.sin_addr.s_addr = INADDR_ANY;
bind(s, (struct sockaddr*)&server_addr, sizeof(server_addr));
listen(s, SOMAXCONN);
cout << "等待客户端连接..." << endl;
while (true)
{
int client_s = accept(s, NULL, NULL);
cout << "客户端已连接!" << endl;
char buf[1024] = { 0 };
recv(client_s, buf, sizeof(buf), 0);
cout << "收到客户端消息:" << buf << endl;
send(client_s, buf, strlen(buf), 0);
close(client_s);
cout << "客户端已断开连接!" << endl;
}
close(s);
return 0;
}
```
Linux下C++使用多线程技术实现多客户端并发访问指定服务器 客户端和服务端代码
以下是一个简单的多线程 C++ 客户端和服务端代码,可以实现多客户端并发访问指定服务器:
### 服务端代码
```c++
#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
#include <cstring>
#include <cstdlib>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <pthread.h>
using namespace std;
#define PORT 8888
#define MAX_CLIENTS 10
#define BUFFER_SIZE 1024
void* handle_client(void* client_socket_void_ptr) {
int client_socket = *(int*)client_socket_void_ptr;
char buffer[BUFFER_SIZE];
while (true) {
memset(buffer, 0, sizeof(buffer));
int bytes_received = recv(client_socket, buffer, sizeof(buffer), 0);
if (bytes_received == -1) {
cerr << "Error in recv." << endl;
close(client_socket);
return NULL;
} else if (bytes_received == 0) {
cout << "Client disconnected." << endl;
close(client_socket);
return NULL;
}
cout << "Received: " << buffer << endl;
string response = "Server received: ";
response += buffer;
int bytes_sent = send(client_socket, response.c_str(), response.length(), 0);
if (bytes_sent == -1) {
cerr << "Error in send." << endl;
close(client_socket);
return NULL;
}
}
}
int main() {
int server_socket = socket(AF_INET, SOCK_STREAM, 0);
if (server_socket == -1) {
cerr << "Error creating server socket." << endl;
return 1;
}
sockaddr_in server_address;
server_address.sin_family = AF_INET;
server_address.sin_port = htons(PORT);
server_address.sin_addr.s_addr = INADDR_ANY;
if (bind(server_socket, (sockaddr*)&server_address, sizeof(server_address)) == -1) {
cerr << "Error binding server socket." << endl;
return 1;
}
if (listen(server_socket, MAX_CLIENTS) == -1) {
cerr << "Error listening on server socket." << endl;
return 1;
}
cout << "Server started. Listening on port " << PORT << "." << endl;
while (true) {
sockaddr_in client_address;
socklen_t client_address_size = sizeof(client_address);
int client_socket = accept(server_socket, (sockaddr*)&client_address, &client_address_size);
if (client_socket == -1) {
cerr << "Error accepting client socket." << endl;
continue;
}
cout << "Client connected from " << inet_ntoa(client_address.sin_addr) << ":" << ntohs(client_address.sin_port) << "." << endl;
pthread_t thread;
if (pthread_create(&thread, NULL, handle_client, &client_socket) != 0) {
cerr << "Error creating thread." << endl;
close(client_socket);
continue;
}
pthread_detach(thread);
}
close(server_socket);
return 0;
}
```
### 客户端代码
```c++
#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
#include <cstring>
#include <cstdlib>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <pthread.h>
using namespace std;
#define PORT 8888
#define BUFFER_SIZE 1024
void* receive_messages(void* socket_void_ptr) {
int socket = *(int*)socket_void_ptr;
char buffer[BUFFER_SIZE];
while (true) {
memset(buffer, 0, sizeof(buffer));
int bytes_received = recv(socket, buffer, sizeof(buffer), 0);
if (bytes_received == -1) {
cerr << "Error in recv." << endl;
close(socket);
exit(1);
} else if (bytes_received == 0) {
cout << "Server disconnected." << endl;
close(socket);
exit(0);
}
cout << "Received: " << buffer << endl;
}
}
int main(int argc, char** argv) {
if (argc != 2) {
cerr << "Usage: " << argv[0] << " <server_ip_address>" << endl;
return 1;
}
int client_socket = socket(AF_INET, SOCK_STREAM, 0);
if (client_socket == -1) {
cerr << "Error creating client socket." << endl;
return 1;
}
sockaddr_in server_address;
server_address.sin_family = AF_INET;
server_address.sin_port = htons(PORT);
if (inet_pton(AF_INET, argv[1], &server_address.sin_addr) == -1) {
cerr << "Error converting server IP address." << endl;
return 1;
}
if (connect(client_socket, (sockaddr*)&server_address, sizeof(server_address)) == -1) {
cerr << "Error connecting to server." << endl;
return 1;
}
cout << "Connected to server " << argv[1] << ":" << PORT << "." << endl;
pthread_t thread;
if (pthread_create(&thread, NULL, receive_messages, &client_socket) != 0) {
cerr << "Error creating thread." << endl;
close(client_socket);
return 1;
}
string message;
while (true) {
getline(cin, message);
if (message.length() == 0) {
continue;
}
int bytes_sent = send(client_socket, message.c_str(), message.length(), 0);
if (bytes_sent == -1) {
cerr << "Error in send." << endl;
close(client_socket);
return 1;
}
}
close(client_socket);
return 0;
}
```
在 Linux 系统中编译这些代码可以使用以下命令:
```
g++ -pthread server.cpp -o server
g++ -pthread client.cpp -o client
```
然后分别运行 `server` 和 `client` 可执行文件即可。