写一个简单的多线程Cpp代码

Sure, here is a simple multi-threaded C++ code:

#include <iostream>
#include <thread>

using namespace std;

void printHello() {
    cout << "Hello from thread " << this_thread::get_id() << endl;
}

int main() {
    thread t1(printHello);
    thread t2(printHello);

    t1.join();
    t2.join();

    return 0;
}

This code creates two threads using the `thread` class and passes a function `printHello` to each thread. Each thread will print a message indicating which thread it is running on using the `this_thread::get_id()` function. The `join()` method is used to wait for the threads to finish executing before the program exits.

Hope that helps!