Challenge 1: A Basic Suspend Function with launch — Solution

import kotlinx.coroutines.*

suspend fun printAfterDelay(message: String, delayMs: Long) {
    delay(delayMs)
    println(message)
}

fun main() = runBlocking {
    val job = launch {
        printAfterDelay("Delayed message!", 1000)
    }
    println("Launched")
    job.join()
    println("Program finished")
}

/*
Output:
Launched
Delayed message!      (printed ~1 second later)
Program finished

Notes:
- printAfterDelay is a suspend function, so it can only be called from
  inside a coroutine (here, the lambda passed to launch).
- launch starts a new coroutine that begins running immediately but
  doesn't block main() — "Launched" prints right away, before the
  1-second delay finishes.
- job.join() suspends runBlocking's coroutine until the launched
  coroutine completes, which is why "Program finished" only prints after
  "Delayed message!" — without join(), the program could exit before the
  launched coroutine ever got to run.
*/