Challenge 2: Concurrent async Calls — Solution

import kotlinx.coroutines.*

suspend fun fetchTemperature(): Int {
    delay(500)
    return 21
}

suspend fun fetchHumidity(): Int {
    delay(500)
    return 55
}

fun main() = runBlocking {
    val temperatureDeferred = async { fetchTemperature() }
    val humidityDeferred = async { fetchHumidity() }

    val temperature = temperatureDeferred.await()
    val humidity = humidityDeferred.await()

    println("Temperature: $temperature, Humidity: $humidity")
    // Both async calls start immediately and run concurrently, so the
    // whole thing takes ~500ms total, not ~1000ms (500ms + 500ms) as it
    // would if fetchHumidity() only started after fetchTemperature()
    // finished.
}

/*
Output:
Temperature: 21, Humidity: 55
(takes roughly 500ms to run, not 1000ms)

Notes:
- Both async { ... } calls start their coroutines immediately when async
  is called, not when await() is called — await() only suspends until
  that specific coroutine's result is ready.
- Because both delays overlap in time rather than happening one after
  another, the total wait is the length of the longer delay (500ms), not
  the sum of both (1000ms).
*/