---

interface Playable {
    fun play(): String
    fun stop(): String = "Воспроизведение остановлено"
}

sealed class MediaItem : Playable {
    data class Song(
        val title: String,
        val artist: String,
        val durationSec: Int,
        val genre: String
    ) : MediaItem() {
        override fun play(): String = "Играет: $title — $artist [$genre]"
    }

    data class Podcast(
        val title: String,
        val host: String,
        val durationSec: Int,
        val episodeNumber: Int
    ) : MediaItem() {
        override fun play(): String = "Подкаст $episodeNumber: $title — ведущий $host"
    }

    data class Audiobook(
        val title: String,
        val author: String,
        val durationSec: Int,
        val chapter: Int
    ) : MediaItem() {
        override fun play(): String = "Аудиокнига $author — $title, глава $chapter"
    }
}

object PlaylistManager {
    fun createDefaultPlaylist(): List<MediaItem> {
        return listOf(
            MediaItem.Song("Bohemian Rhapsody", "Queen", 354, "Rock"),
            MediaItem.Song("Shape of You", "Ed Sheeran", 233, "Pop"),
            MediaItem.Podcast("IT Новости", "Алексей", 1800, 42),
            MediaItem.Podcast("Дизайн сегодня", "Мария", 2400, 15),
            MediaItem.Audiobook("Мастер и Маргарита", "М. Булгаков", 1200, 1),
            MediaItem.Audiobook("1984", "Дж. Оруэлл", 1500, 3)
        )
    }

    fun findByTitle(playlist: List<MediaItem>, query: String): List<MediaItem> {
        return playlist.filter { item ->
            when (item) {
                is MediaItem.Song -> item.title.contains(query, ignoreCase = true)
                is MediaItem.Podcast -> item.title.contains(query, ignoreCase = true)
                is MediaItem.Audiobook -> item.title.contains(query, ignoreCase = true)
            }
        }
    }
}

fun main() {
    val playlist = PlaylistManager.createDefaultPlaylist()

    println("=== Воспроизведение треков ===")
    for (item in playlist) {
        println(item.play())
        println(item.stop())
    }

    val totalDurationSec = playlist.sumOf { item ->
        when (item) {
            is MediaItem.Song -> item.durationSec
            is MediaItem.Podcast -> item