import java.util.LinkedList import java.util.StringTokenizer fun main() { val br = System.`in`.bufferedReader() val queue = LinkedList() val str = br.readLine() val m = br.readLine().toInt() var index = 0 repeat(m) { val token = StringTokenizer(br.readLine()) when (token.nextToken()) { "L" -> { if (index > 0) index-- } "D" -> { if (index < queue.size) index++ } "B" -> { if (index > 0) { index-- queue.removeAt(index) } } "P" -> { queue.add(index, token.nextToken()) index++ } } } val sb = StringBuilder() for (c in queue) { sb.append(c) } println(sb) }