fun main(args: Array<String>) {
    val N = readInputLine().toInt()
    
    println(0)
    var before = readInputLine()
    if (before.equals("Vacant")) {
        return
    }

    var l = 1
    var r = N
    
    while (l != r) {
        val mid = (l + r) / 2
        
        println(mid)
        val res = readInputLine()
        
        if (res.equals("Vacant")) {
            return
        }
        
        if (mid % 2 == 0) {
            if (res.equals(before)) {
                l = mid + 1
            } else {
                r = mid
            }
        } else {
            if (res.equals(before)) {
                r = mid
            } else {
                l = mid + 1
            }            
        }
    }
}

fun readInputLine(): String {
    return readLine()!!
}
