fun main(args: Array<String>) {
    getAns()?.also {
        println("Possible")
        println(it)
    }?:run {
        println("Impossible")
    }
}

fun getAns():Long? {
    val (a,b,c,d) = readLine()!!.split(" ").map { it.toInt() }
    if(d >= 10) {
        return null
    }
    var adj = 1L
    var remainB = b
    var remainA = a
    var remainCombo = 100
    var score = 0L
    while (remainB > 0) {
        val add = Math.min(remainCombo, remainB)
        score += add*50*adj
        remainCombo -= add
        remainB -= add
        if(remainCombo <= 0) {
            adj*=2
            remainCombo = 100
        }
    }
    while (remainA > 0) {
        val add = Math.min(remainCombo, remainA)
        score += add*100*adj
        remainCombo -= add
        remainA -= add
        if(remainCombo <= 0) {
            adj *= 2
            remainCombo = 100
        }
    }
    return score
}