[백준] 10828. 스택 (Kotlin)

문제 : www.acmicpc.net/problem/10828

10828번: 스택

 

 

fun main() = with(System.`in`.bufferedReader()){
    val stack = arrayListOf<Int>()
    val n = readLine().toInt()

    for(i in 0 until n){
        val tmp = readLine().split(" ")
        when(tmp[0]){
            "push" -> {
                stack.add(tmp[1].toInt())
            }
            "pop" ->{
                if (stack.isNotEmpty()) println(stack.removeAt(stack.size - 1))
                else println("-1")
            }
            "size" ->{
                println(stack.size)
            }
            "empty" ->{
                if (stack.isEmpty()) println("1")
                else println("0")
            }
            "top" -> {
                if (stack.isNotEmpty()) println(stack[stack.size - 1])
                else println("-1")
            }
        }
    }
}