Joining multiple threads without waiting using pthread library and c++

Say the main thread created three worker threads. Suppose all three threads run a function similar to work() below.

bool signal[3]={false};

void* work(void* thread_id)  //each worker thread is given a thread_id when created
{
    int x = *(int*)thread_id;
    int data;
    /*code*/
    signal[x] = true;  //this thread finished
    pthread_exit(&data);
}

Usually I use following code to join the threads.

int main()
{
    pthread_t workerThreads[3];
    int master;
    /* code for creating threads */
    for(int i=0;i<3;i++)
    { 
        void* status;
        master = pthread_join(workerThreads[i],&status);
        /* code for handling the return data from thread*/
    }  
}

What I mean is if workerThreads[2] finished before workerThreads[0] , with the code above, main thread still have to wait for workerThreads[0] finish first before handling workerThreads[2]

Is there a way to join the threads without waiting?

Can I use something like this?

while(!signal[0]||!signal[1]||!signal[2]){
if(signal[0]){/*join workerThreads[0]*/}
if(signal[1]){/*join workerThreads[1]*/}
if(signal[2]){/*join workerThreads[2]*/}
}