fun main() {
    val x = readLine()!!.toDouble()
    val y = readLine()!!.toDouble()
    val l = readLine()!!.toDouble()

    var count = 0.0
    if (y >= 0) {
        count += Math.ceil(y / l)
        if (x != 0.0) {
            count += (1 + Math.ceil(Math.abs(x) / l))
        }
    } else if (y < 0) {
        count += (1 + Math.ceil(Math.abs(x) / l))
        if (y != 0.0) {
            count += (1 + Math.ceil(Math.abs(y) / l))
        }
    }
    println(count.toInt())
}