non_local.kt

fun <A> memoryControl(
        used: AtomicInteger,
        max: Int,
        open: MutableSet<A>,
        fScores: MutableMap<A, Double>,
        depths: Map<A, Double>,
        memoryNeighbors: Map<A, MutableSet<A>>,
        cameFrom: Map<A, A>,
        closed: MutableSet<A>
) {
    if (used.get() == max) {
        val omegaSet = open.maxesBy { fScores[it]!! }
        val worst = omegaSet.filter {
            val neighbors = memoryNeighbors[it]?.size ?: 0
            neighbors == 0
        }.minBy { depths[it] ?: error("need depth for nodes") }!!

        val parent = cameFrom[worst]
        if (parent != null) {
            memoryNeighbors[parent]?.remove(worst) // TODO: this good??? ... should we wipe if size 0
            if (parent in closed) {
                closed.remove(parent)
                open.add(parent)
            }
        }

        used.getAndDecrement()
    }
}