What methods can be used to implement coroutines in programming?

Coroutines are functions that can suspend their execution and resume later, which is convenient for asynchronous programming.

Methods of implementing coroutines:

1. Using async/await keywords (for example, in Kotlin or Python) — allows writing asynchronous code that looks like synchronous code.

2. Generators — functions that return intermediate results using yield and can resume execution.

3. Callbacks and state machines — lower-level methods where the state and calls are managed manually.

4. Libraries and frameworks — for example, in Android, Kotlin Coroutines provide a convenient API for working with coroutines.

Example in Kotlin:

import kotlinx.coroutines.*

fun main() = runBlocking {
    launch {
        delay(1000L)
        println("Coroutine completed")
    }
    println("Starting coroutine")
}