File content as of revision 0:be029d41beb4:

#include "mbed.h"
#include "rtos.h"
 
DigitalOut led1(LED1);
DigitalOut led2(LED2);
DigitalOut led3(LED3);
DigitalOut led4(LED4);

void led1_thread(void const *args) {
    while (true) {
        led1 = !led1;
        Thread::wait((rand()%700)+1);
    }
}

void led2_thread(void const *args) {
    while (true) {
        led2 = !led2;
        Thread::wait((rand()%700)+1);
    }
}

void led3_thread(void const *args) {
    while (true) {
        led3 = !led3;
        Thread::wait((rand()%700)+1);
    }
}

void led4_thread(void const *args) {
    while (true) {
        led4 = !led4;
        Thread::wait((rand()%700)+1);
    }
}
 
int main() {
    //Create a thread to execute the function led2_thread
    Thread thread1(led1_thread);
    Thread thread2(led2_thread);
    Thread thread3(led3_thread);
    Thread thread4(led4_thread);
    
    //led2_thread is executing concurrently with main at this point
    
    while (true) {
    }
}