const val VACANT = "Vacant"

fun main(args: Array<String>) {


    val n = readLine()!!.toInt()

    var l = 0
    var lType = query(0)
    if (lType == VACANT) return

    var u = n
    var uType = lType
    while (true) {
        val m = (l + u) / 2
        var mType = query(m)
        if (mType == VACANT) return
        if (lType == mType) {
            if ((m - l) % 2 == 1) {
                u = m
                uType = mType
            } else {
                l = m
                lType = mType
            }
        } else {
            if ((m - l) % 2 == 0) {
                u = m
                uType = mType
            } else {
                l = m
                lType = mType
            }
        }
    }
}

fun query(position: Int): String {
    println(position)
    return readLine()!!
}
