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lvguowei/gist:c44effdb034abd99094e30d60d695289

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A little java, a few patterns
Raw
gistfile1.kt
import java.util.*
import kotlin.math.sqrt
abstract class Point(val x: Int, val y: Int) {
abstract fun distanceToO(): Double
fun closerToO(p: Point) = distanceToO() < p.distanceToO()
fun minus(p: Point) = CartesianPt(x - p.x, y - p.y)
}
open class CartesianPt(x: Int, y: Int) : Point(x, y) {
override fun distanceToO() = sqrt((x * x + y * y).toDouble())
}
open class ManhattanPt(x: Int, y: Int) : Point(x, y) {
override fun distanceToO() = (x + y).toDouble()
}
class ShadowedManhattanPt(x: Int, y: Int, private val dx: Int, private val dy: Int) : ManhattanPt(x, y) {
override fun distanceToO() = (super.distanceToO() + dx + dy)
}
class ShadowedCartesianPt(x: Int, y: Int, private val dx: Int, private val dy: Int) : CartesianPt(x, y) {
override fun distanceToO() = CartesianPt(x + dx, y + dy).distanceToO()
}
abstract class Layer
class Base(val o: Any) : Layer()
class Slice(val l: Layer) : Layer()
abstract class Shish {
val ooFn = OnlyOnionsVisitor()
val ivFn = IsVegetarianVisitor()
abstract fun onlyOnions(): Boolean
abstract fun isVegetarian(): Boolean
}
class Skewer : Shish() {
override fun onlyOnions() = ooFn.forSkewer()
override fun isVegetarian() = ivFn.forSkewer()
}
class Onion(val s: Shish) : Shish() {
override fun onlyOnions() = ooFn.forOnion(s)
override fun isVegetarian() = ivFn.forOnion(s)
}
class Lamb(val s: Shish) : Shish() {
override fun onlyOnions() = ooFn.forLamb(s)
override fun isVegetarian() = ivFn.forLamb(s)
}
class Tomato(val s: Shish) : Shish() {
override fun onlyOnions() = ooFn.forTomato(s)
override fun isVegetarian() = ivFn.forTomato(s)
}
class OnlyOnionsVisitor {
fun forSkewer() = true
fun forOnion(s: Shish) = s.onlyOnions()
fun forLamb(s: Shish) = false
fun forTomato(s: Shish) = false
}
class IsVegetarianVisitor {
fun forSkewer() = true
fun forOnion(s: Shish) = s.isVegetarian()
fun forLamb(s: Shish) = false
fun forTomato(s: Shish) = s.isVegetarian()
}
abstract class Kebab {
abstract fun isVeggie(): Boolean
abstract fun whatHolder(): Any
}
class Holder(private val o: Any) : Kebab() {
override fun isVeggie() = true
override fun whatHolder() = o
}
class Shallot(private val k: Kebab) : Kebab() {
override fun isVeggie() = k.isVeggie()
override fun whatHolder() = k.whatHolder()
}
class Shrimp(private val k: Kebab) : Kebab() {
override fun isVeggie() = false
override fun whatHolder() = k.whatHolder()
}
class Radish(private val k: Kebab) : Kebab() {
override fun isVeggie() = k.isVeggie()
override fun whatHolder() = k.whatHolder()
}
class Pepper(private val k: Kebab) : Kebab() {
override fun isVeggie() = k.isVeggie()
override fun whatHolder() = k.whatHolder()
}
abstract class Rod
class Dagger : Rod()
class Sabre : Rod()
class Sword : Rod()
abstract class Plate
class Gold : Plate()
class Silver : Plate()
class Brass : Plate()
class Copper : Plate()
class Wood : Plate()
abstract class Pizza {
val remFn = RemoveAnchovyVisitor()
val topFn = TopAnchovyWithCheeseVisitor()
val subFn = SubstituteAnchovyByCheeseVisitor()
abstract fun removeAnchovy(): Pizza
abstract fun topAnchovyWithCheese(): Pizza
abstract fun substituteAnchovyByCheese(): Pizza
}
class SubstituteAnchovyByCheeseVisitor {
fun forCrust() = Crust()
fun forCheese(p: Pizza) = Cheese(p.substituteAnchovyByCheese())
fun forOlive(p: Pizza) = Olive(p.substituteAnchovyByCheese())
fun forAnchovy(p: Pizza) = Cheese(p.substituteAnchovyByCheese())
fun forSausage(p: Pizza) = Sausage(p.substituteAnchovyByCheese())
fun forSpinach(p: Pizza) = Spinach(p.substituteAnchovyByCheese())
}
class TopAnchovyWithCheeseVisitor {
fun forCrust() = Crust()
fun forCheese(p: Pizza) = Cheese(p.topAnchovyWithCheese())
fun forOlive(p: Pizza) = Olive(p.topAnchovyWithCheese())
fun forAnchovy(p: Pizza) = Cheese(Anchovy(p.topAnchovyWithCheese()))
fun forSausage(p: Pizza) = Sausage(p.topAnchovyWithCheese())
fun forSpinach(p: Pizza) = Spinach(p.topAnchovyWithCheese())
}
class RemoveAnchovyVisitor {
fun forCrust() = Crust()
fun forCheese(p: Pizza) = Cheese(p.removeAnchovy())
fun forOlive(p: Pizza) = Olive(p.removeAnchovy())
fun forAnchovy(p: Pizza) = p.removeAnchovy()
fun forSausage(p: Pizza) = Sausage(p.removeAnchovy())
fun forSpinach(p: Pizza) = Spinach(p.removeAnchovy())
}
class Crust : Pizza() {
override fun removeAnchovy() = remFn.forCrust()
override fun topAnchovyWithCheese() = topFn.forCrust()
override fun substituteAnchovyByCheese() = subFn.forCrust()
}
class Cheese(val p: Pizza) : Pizza() {
override fun removeAnchovy() = remFn.forCheese(p)
override fun topAnchovyWithCheese() = topFn.forCheese(p)
override fun substituteAnchovyByCheese() = subFn.forCheese(p)
}
class Olive(val p: Pizza) : Pizza() {
override fun removeAnchovy() = remFn.forOlive(p)
override fun topAnchovyWithCheese() = topFn.forOlive(p)
override fun substituteAnchovyByCheese() = subFn.forOlive(p)
}
class Anchovy(val p: Pizza) : Pizza() {
override fun removeAnchovy() = remFn.forAnchovy(p)
override fun topAnchovyWithCheese() = topFn.forAnchovy(p)
override fun substituteAnchovyByCheese() = subFn.forAnchovy(p)
}
class Sausage(val p: Pizza) : Pizza() {
override fun removeAnchovy() = remFn.forSausage(p)
override fun topAnchovyWithCheese() = topFn.forSausage(p)
override fun substituteAnchovyByCheese() = subFn.forSausage(p)
}
class Spinach(val p: Pizza) : Pizza() {
override fun removeAnchovy(): Pizza = remFn.forSpinach(p)
override fun topAnchovyWithCheese() = topFn.forSpinach(p)
override fun substituteAnchovyByCheese() = subFn.forSpinach(p)
}
abstract class Pie {
abstract fun accept(ask: PieVisitor): Pie
}
interface PieVisitor {
fun forBot(): Pie
fun forTop(t: Any, r: Pie): Pie
}
class RemV(private val o: Any) : PieVisitor {
override fun forBot() = Bot()
override fun forTop(t: Any, r: Pie) =
if (o == t)
r.accept(this)
else Top(t, r.accept(this))
}
open class SubstV(private val n: Any, private val o: Any): PieVisitor {
override fun forBot() = Bot()
override fun forTop(t: Any, r: Pie) =
if (o == t)
Top(n, r.accept(this))
else Top(t, r.accept(this))
}
class LtdSubstV(private val c: Int, private val n: Any, private val o: Any) : SubstV(n, o) {
override fun forTop(t: Any, r: Pie) =
if (c == 0) {
Top(t, r)
} else if (o == t) {
Top(n, r.accept(LtdSubstV(c - 1, n, o)))
} else {
Top(t, r.accept(this))
}
}
class Bot : Pie() {
override fun accept(ask: PieVisitor) = ask.forBot()
override fun toString(): String {
return "Bottom |"
}
}
class Top(private val t: Any, private val r: Pie) : Pie() {
override fun accept(ask: PieVisitor) = ask.forTop(t, r)
override fun toString(): String {
return "$t <<< $r"
}
}
abstract class Fish
class Anchovy2 : Fish() {
override fun equals(other: Any?): Boolean {
if (this === other) return true
if (javaClass != other?.javaClass) return false
return true
}
override fun hashCode(): Int {
return javaClass.hashCode()
}
}
class Salmon : Fish() {
override fun equals(other: Any?): Boolean {
if (this === other) return true
if (javaClass != other?.javaClass) return false
return true
}
override fun hashCode(): Int {
return javaClass.hashCode()
}
}
class Tuna : Fish() {
override fun equals(other: Any?): Boolean {
if (this === other) return true
if (javaClass != other?.javaClass) return false
return true
}
override fun hashCode(): Int {
return javaClass.hashCode()
}
}
abstract class Fruit
class Peach : Fruit() {
override fun equals(other: Any?): Boolean {
return other is Peach
}
}
class Apple : Fruit() {
override fun equals(other: Any?): Boolean {
return other is Apple
}
}
class Pear : Fruit() {
override fun equals(other: Any?): Boolean {
return other is Pear
}
}
class Lemon : Fruit() {
override fun equals(other: Any?): Boolean {
return other is Lemon
}
}
class Fig : Fruit() {
override fun equals(other: Any?): Boolean {
return other is Fig
}
}
abstract class Tree {
abstract fun accept(ask: TreeVisitor): Any
}
class Bud : Tree() {
override fun accept(ask: TreeVisitor) = ask.forBud()
}
class Flat(private val f: Fruit, private val t: Tree) : Tree() {
override fun accept(ask: TreeVisitor) = ask.forFlat(f, t)
}
class Split(private val l: Tree, private val r: Tree) : Tree() {
override fun accept(ask: TreeVisitor) = ask.forSplit(l, r)
}
interface TreeVisitor {
fun forBud(): Any
fun forFlat(f: Fruit, t: Tree): Any
fun forSplit(l: Tree, r: Tree): Any
}
class IsFlat : TreeVisitor {
override fun forBud() = true
override fun forFlat(f: Fruit, t: Tree) = t.accept(this)
override fun forSplit(l: Tree, r: Tree) = false
}
class IsSplit : TreeVisitor {
override fun forBud() = true
override fun forFlat(f: Fruit, t: Tree) = false
override fun forSplit(l: Tree, r: Tree) = (l.accept(this) as Boolean) && (r.accept(this) as Boolean)
}
class Occurs(private val a: Fruit) : TreeVisitor {
override fun forBud() = 0
override fun forFlat(f: Fruit, t: Tree) =
if (a == f) {
(t.accept(this) as Int) + 1
} else {
t.accept(this)
}
override fun forSplit(l: Tree, r: Tree) = (l.accept(this) as Int) + (r.accept(this) as Int)
}
abstract class Expr {
abstract fun accept(ask: ExprVisitor): Any
}
class Plus(private val l: Expr, private val r: Expr) : Expr() {
override fun accept(ask: ExprVisitor) = ask.forPlus(l, r)
}
class Diff(private val l: Expr, private val r: Expr) : Expr() {
override fun accept(ask: ExprVisitor) = ask.forDiff(l, r)
}
class Prod(private val l: Expr, private val r: Expr) : Expr() {
override fun accept(ask: ExprVisitor) = ask.forProd(l, r)
}
class Const(private val c: Any) : Expr() {
override fun accept(ask: ExprVisitor) = ask.forConst(c)
}
interface ExprVisitor {
fun forPlus(l: Expr, r: Expr): Any
fun forDiff(l: Expr, r: Expr): Any
fun forProd(l: Expr, r: Expr): Any
fun forConst(c: Any): Any
}
abstract class Eval : ExprVisitor {
override fun forPlus(l: Expr, r: Expr) = plus(l.accept(this), r.accept(this))
override fun forDiff(l: Expr, r: Expr) = diff(l.accept(this), r.accept(this))
override fun forProd(l: Expr, r: Expr) = prod(l.accept(this), r.accept(this))
override fun forConst(c: Any) = c
abstract fun plus(l: Any, r: Any): Any
abstract fun diff(l: Any, r: Any): Any
abstract fun prod(l: Any, r: Any): Any
}
class IntEval : Eval() {
override fun plus(l: Any, r: Any) = l as Int + r as Int
override fun diff(l: Any, r: Any) = l as Int - r as Int
override fun prod(l: Any, r: Any) = l as Int * r as Int
}
abstract class Set {
fun add(i: Int) = if (mem(i)) this else Add(i, this)
abstract fun mem(n: Int): Boolean
abstract fun plus(t: Set): Set
abstract fun diff(t: Set): Set
abstract fun prod(t: Set): Set
}
class Empty : Set() {
override fun mem(n: Int) = false
override fun plus(t: Set) = t
override fun diff(t: Set) = Empty()
override fun prod(t: Set) = Empty()
override fun toString() = "."
}
class Add(private val i: Int, private val s: Set) : Set() {
override fun mem(n: Int) = if (i == n) true else s.mem(n)
override fun plus(t: Set) = s.plus(t.add(i))
override fun diff(t: Set) = if (t.mem(i)) s.diff(t) else s.diff(t).add(i)
override fun prod(t: Set) = if (t.mem(i)) s.prod(t).add(i) else s.prod(t)
override fun toString() = "$i $s"
}
class SetEval : Eval() {
override fun plus(l: Any, r: Any) = (l as Set).plus(r as Set)
override fun diff(l: Any, r: Any) = (l as Set).diff(r as Set)
override fun prod(l: Any, r: Any) = (l as Set).prod(r as Set)
}
abstract class Shape {
abstract fun accept(ask: ShapeVisitor): Boolean
}
class Circle(private val r: Int) : Shape() {
override fun accept(ask: ShapeVisitor) = ask.forCircle(r)
}
class Square(private val s: Int) : Shape() {
override fun accept(ask: ShapeVisitor) = ask.forSquare(s)
}
class Trans(private val q: Point, private val s: Shape) : Shape() {
override fun accept(ask: ShapeVisitor) = ask.forTrans(q, s)
}
class Union(private val s: Shape, private val t: Shape) : Shape() {
override fun accept(ask: ShapeVisitor) = (ask as UnionVisitor).forUnion(s, t)
}
interface ShapeVisitor {
fun forCircle(r: Int): Boolean
fun forSquare(s: Int): Boolean
fun forTrans(q: Point, s: Shape): Boolean
}
interface UnionVisitor : ShapeVisitor {
fun forUnion(s: Shape, t: Shape): Boolean
}
open class HasPt(private val p: Point) : ShapeVisitor {
override fun forCircle(r: Int) = p.distanceToO() <= r
override fun forSquare(s: Int) = p.x <= s && p.y <= s
open fun newHasPt(p: Point) = HasPt(p)
override fun forTrans(q: Point, s: Shape) = s.accept(newHasPt(p.minus(q)))
}
class UnionHasPt(p: Point) : HasPt(p), UnionVisitor {
override fun newHasPt(p: Point) = UnionHasPt(p)
override fun forUnion(s: Shape, t: Shape) = s.accept(this) || t.accept(this)
}
abstract class PieD {
abstract fun accept(ask: PieVisitorI): Any
}
class Bot2 : PieD() {
override fun accept(ask: PieVisitorI) = ask.forBot()
}
class Top2(private val t: Any, private val r: PieD) : PieD() {
override fun accept(ask: PieVisitorI) = ask.forTop(t, r)
}
interface PieVisitorI {
fun forBot(): Any
fun forTop(t: Any, r: PieD): Any
}
class OccursV(private val a: Any) : PieVisitorI {
override fun forBot() = 0
override fun forTop(t: Any, r: PieD) =
if (t == a) {
r.accept(this) as Int + 1
} else {
r.accept(this)
}
}
class SubstV2(private val n: Any, private val o: Any) : PieVisitorI {
override fun forBot() = Bot()
override fun forTop(t: Any, r: PieD) =
if (o == t)
Top2(n, r.accept(this) as PieD)
else
Top2(t, r.accept(this) as PieD)
}
class RemV2(private val o: Any) : PieVisitorI {
override fun forBot() = Bot()
override fun forTop(t: Any, r: PieD) =
if (t == o)
r.accept(this)
else
Top2(t, r.accept(this) as PieD)
}
interface PiemanI {
fun addTop(t: Any): Int
fun remTop(t: Any): Int
fun substTop(n: Any, o: Any): Int
fun occTop(o: Any): Int
}
class PiemanM : PiemanI {
private var p: PieD = Bot2()
override fun addTop(t: Any): Int {
p = Top2(t, p)
return occTop(t)
}
override fun remTop(t: Any): Int {
p = p.accept(RemV2(t)) as PieD
return occTop(t)
}
override fun substTop(n: Any, o: Any): Int {
p = p.accept(SubstV2(n, o)) as PieD
return occTop(n)
}
override fun occTop(o: Any) = p.accept(OccursV(o)) as Int
}
fun main(args: Array<String>) {
// println(ManhattanPt(3, 4).distanceToO())
// println(CartesianPt(3, 4).distanceToO())
// println(Top(Anchovy2(), Top(Salmon(), Top(Anchovy2(), Top(Tuna(), Bot())))).accept(RemoveVisitor(Anchovy2())))
// println(Top(Anchovy2(), Top(Salmon(), Top(Anchovy2(), Top(Tuna(), Bot())))).accept(SubstituteVisitor(Anchovy2(), Salmon())))
// println(Top(Anchovy2(), Top(Anchovy2(), Top(Anchovy2(), Top(Tuna(), Bot())))).accept(LtdSubstituteVisitor(2, Salmon(), Anchovy2())))
// println(Plus(Prod(Const(1), Const(2)), Const(3)).accept(IntEval()))
// println(Plus(Prod(Const(Empty().add(1).add(2)), Const(Empty().add(2).add(3))), Const(Empty().add(3))).accept(SetEval()))
Trans(
CartesianPt(3, 7),
Union(
Square(10),
Circle(10)
)
).accept(UnionHasPt(CartesianPt(13, 17)))
}
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