What is the maximum number of threads that can work in parallel in the program below?
SlackerThread is a class representing a thread that sleeps a random number of seconds after the start.
Tip: Don't forget about the main thread.
fun main() {
val t1 = SlackerThread()
val t2 = SlackerThread()
t1.start()
t2.start()
t2.join()
val t3 = SlackerThread()
val t4 = SlackerThread()
t3.start()
t4.start()
t3.join()
t4.join()
}