Решение

import java.io.BufferedReader
import java.io.BufferedWriter
import java.io.InputStreamReader
import java.io.OutputStreamWriter

fun main() {
    val reader = BufferedReader(InputStreamReader(System.`in`))
    val writer = BufferedWriter(OutputStreamWriter(System.out))

    val n = reader.readLine().toInt() // Количество связей между складами
    val graph = mutableMapOf<Int, MutableList<Int>>()

    // Считываем связи между складами и формируем граф
    repeat(n) {
        val (u, v) = reader.readLine().split(" ").map { it.toInt() }
        graph.computeIfAbsent(u) { mutableListOf() }.add(v)
        graph.computeIfAbsent(v) { mutableListOf() }.add(u)
    }

    // Поиск компонент связности (кластеры складов)
    val warehouseCluster = mutableMapOf<Int, Int>()
    var clusterId = 0

    fun dfs(node: Int) {
        val stack = mutableListOf(node)
        while (stack.isNotEmpty()) {
            val current = stack.removeLast()
            if (current in warehouseCluster) continue
            warehouseCluster[current] = clusterId
            graph[current]?.forEach { stack.add(it) }
        }
    }

    for (warehouse in graph.keys) {
        if (warehouse !in warehouseCluster) {
            dfs(warehouse)
            clusterId++
        }
    }

    val t = reader.readLine().toInt() // Количество запросов

    repeat(t) {
        val (x, k) = reader.readLine().split(" ").map { it.toInt() }
        val suppliers = reader.readLine().split(" ").map { it.toInt() }

        val validSuppliers = suppliers.filter { warehouseCluster[it] == warehouseCluster[x] }
        writer.write("${validSuppliers.size} ${validSuppliers.joinToString(" ")}\\n")
    }

    writer.flush()
    reader.close()
    writer.close()
}