2019 Day 19 Begun

2019/day19/main.go

@@ -0,0 +1,185 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+	"time"
+
+	intcode "git.bullercodeworks.com/brian/adventofcode/2019/intcode-processor"
+	helpers "git.bullercodeworks.com/brian/adventofcode/helpers"
+)
+
+var beam map[string]int
+var maxY int
+
+func main() {
+	pt := helpers.GetArgNumber(1)
+	prog := intcode.ReadIntCodeFile("input")
+	beam = make(map[string]int)
+	if pt == "1" {
+		part1(prog)
+	} else {
+		part2(prog)
+	}
+}
+
+func part1(prog []int) {
+	var count int
+	var lastRowStart int
+	for y := 0; y < 50; y++ {
+		var foundFirst bool
+		fmt.Print(strings.Repeat(" ", lastRowStart))
+		for x := lastRowStart; x < 50; x++ {
+			out := runCodeAt(prog, x, y)
+			fmt.Print(out)
+			beam[c(x, y)] = out
+			if out == 1 {
+				if !foundFirst {
+					lastRowStart = x
+				}
+				foundFirst = true
+				count++
+			} else if foundFirst {
+				break
+			}
+		}
+		fmt.Println()
+		maxY = y
+	}
+	fmt.Println("Total:", count)
+}
+
+func part2(prog []int) {
+	shipSize := 100
+	// Guesses
+	//x, y := 0, 1000
+	var x, square int
+	bot, _ := 1025, 1037
+	for square != shipSize {
+		bot++
+		fmt.Print("Calculating ", bot, "... ")
+		square, x = maxSquare(prog, bot, bot/2)
+		fmt.Println(square)
+	}
+	fmt.Println(x, bot)
+}
+
+func part2Almost(prog []int) {
+	shipSize := 100
+	// Guesses
+	x, y := 0, 1000
+	var square int
+	bot, top := 1026, 1037
+	square, x = maxSquare(prog, y, 0)
+	lastCheckRow := y
+	for {
+		if square > shipSize {
+			y = y - (y-bot)/2
+		} else if square < shipSize {
+			y = y + (top-y)/2
+		}
+		if lastCheckRow == y {
+			break
+		}
+		lastCheckRow = y
+		fmt.Print("Calculating at ", y, "... ")
+		square, x = maxSquare(prog, y, (y / 2))
+		if square > 100 && y < top {
+			top = y
+		} else if square < 100 && y > bot {
+			bot = y
+		}
+		fmt.Println("Square:", square)
+	}
+	fmt.Println("Final Square:", square)
+	fmt.Println(x, y)
+}
+
+func part2Slow(prog []int) {
+	shipSize := 100
+	var x, y int
+	retX, retY := -1, -1
+	var lastRowStart int
+	for y = maxY; true; y++ {
+		var foundFirst bool
+		fmt.Print(strings.Repeat(" ", lastRowStart))
+		for x = lastRowStart; x < y; x++ {
+			out := runCodeAt(prog, x, y)
+			fmt.Print(out)
+			beam[c(x, y)] = out
+			if out == 1 {
+				if !foundFirst {
+					lastRowStart = x
+				}
+				foundFirst = true
+			} else if foundFirst {
+				break
+			}
+		}
+		square, _ := maxSquare(prog, y, lastRowStart)
+		fmt.Println(":", square)
+		// Every row, check what the maximum square is
+		if square >= shipSize {
+			retY, retX = y, lastRowStart
+			break
+		}
+	}
+	fmt.Println(retX, ",", retY)
+}
+
+// maxSquare returns the square size and the bottom-left x position it starts at
+func maxSquare(prog []int, row, firstX int) (int, int) {
+	for ; firstX < row; firstX++ {
+		// Find the first X
+		if runCodeAt(prog, firstX, row) == 0 {
+			continue
+		}
+
+		var square int
+		for d := 0; true; d++ {
+			if runCodeAt(prog, firstX+d, row-d) == 0 {
+				return square, firstX
+			}
+			square++
+		}
+	}
+	return 0, firstX
+}
+
+func runCodeAt(prog []int, x, y int) int {
+	// If we've already cached this pos, just return it
+	if v, ok := beam[c(x, y)]; ok {
+		return v
+	}
+
+	var res int
+	p := intcode.NewProgram(prog)
+	go func() {
+		sendInputs(p, []int{x, y})
+		res = getOutput(p)
+	}()
+	p.Run()
+
+	beam[c(x, y)] = res
+	return res
+}
+
+func sendInputs(p *intcode.Program, inp []int) {
+	for k := range inp {
+		for !p.NeedsInput() {
+			time.Sleep(1)
+		}
+		p.Input(inp[k])
+	}
+}
+
+func getOutput(p *intcode.Program) int {
+	for !p.NeedsOutput() {
+		time.Sleep(1)
+	}
+	return p.Output()
+}
+
+func c(x, y int) string {
+	return fmt.Sprintf("[%d, %d]", x, y)
+}