fun main() {
    var (a, b, c) = readLongs()
    var bought = false
    while (true) {
        val x = readln()
        if (x == "end") break
        b -= (a - c)
        when {
            bought -> println("self")
            b <= 0 -> {
                bought = true
                println("buy")
            }
            else -> {
                println("airline")
            }
        }
        System.out.flush()
    }
}

private fun readLongs() = readStrings().map { it.toLong() }
private fun readStrings() = readln().split(" ")