2022 Day 20 Complete!

2022/day15/main.go

@@ -5,6 +5,7 @@ import (
 	"math"
 	"os"
 	"strings"
+	"time"
 
 	h "git.bullercodeworks.com/brian/adventofcode/helpers"
 )
@@ -42,8 +43,12 @@ func main() {
 		}
 	}
 
-	part1(inp)
-	part2(inp)
+	if part == 1 || part == -1 {
+		part1(inp)
+	}
+	if part == 2 || part == -1 {
+		part2(inp)
+	}
 }
 
 func part1(inp []string) {
@@ -74,49 +79,122 @@ func part1(inp []string) {
 	fmt.Println(nopeCount)
 }
 
+type Sensor struct {
+	c h.Coordinate // Sensor Position
+	b h.Coordinate // Beacon Position
+	d int          // Distance
+}
+
+func (s Sensor) isInRange(c h.Coordinate) bool { return s.c.Distance(c) <= s.d }
+
+func (s Sensor) String() string { return s.c.String() }
+
 func part2(inp []string) {
-	min_x, max_x := math.MaxInt, math.MinInt
-	var spots [][]int
+	var sensors []Sensor
 	for i := range inp {
-		s, b := strToCoords(inp[i])
-		xs, ys, xb, yb := s.X, s.Y, b.X, b.Y
-		dist := s.Distance(b)
-		l, r := xs-dist, xs+dist
-		min_x = h.Min(min_x, l)
-		max_x = h.Max(max_x, r)
-		spots = append(spots, []int{xs, ys, xb, yb, dist})
+		s := Sensor{}
+		s.c, s.b = strToCoords(inp[i])
+		s.d = s.c.Distance(s.b)
+		sensors = append(sensors, s)
 	}
 
 	max := testRow * 2
-	var found h.Coordinate
-SEARCH:
-	for y := 0; y <= max; y++ {
-		for x := 0; x <= max; x++ {
-			fmt.Printf("Testing %d,%d...", x, y)
-			var nope bool
-			for _, c := range spots {
-				if x == c[2] && y == c[3] {
-					break
-				}
-				if h.ManhattanDistance(x, y, c[0], c[1]) <= c[4] {
-					nope = true
-					break
+	found := []h.Coordinate{}
+	// Check around each sensor, the beacon must be it's distance + 1
+	for _, sensor := range sensors {
+		d := sensor.d + 1
+		testEnds := []h.Coordinate{
+			{X: sensor.c.X, Y: sensor.c.Y - d},
+			{X: sensor.c.X + d, Y: sensor.c.Y},
+			{X: sensor.c.X, Y: sensor.c.Y + d},
+			{X: sensor.c.X - d, Y: sensor.c.Y},
+		}
+		printMap(sensors, max, max, h.Coordinate{X: math.MinInt, Y: math.MinInt})
+		var tstX, tstY int
+		for i := 0; i < 3; i++ {
+			// Test all spots between testEnds[i] & testEnds[i+1]
+			for tstX != testEnds[i+1].X && tstY != testEnds[i+1].Y {
+				if testEnds[i].X < testEnds[i+1].X {
+					tstX++
+					if testEnds[i].Y < testEnds[i+1].Y {
+						tstY++
+					} else {
+						tstY--
+					}
+				} else {
+					tstX--
+					if testEnds[i].Y < testEnds[i+1].Y {
+						tstY++
+					} else {
+						tstY--
+					}
 				}
 			}
-			if !nope {
-				fmt.Println("Yup")
-				found = h.Coordinate{X: x, Y: y}
-				break SEARCH
+			if tstX <= max && tstY <= max {
+				fmt.Print(h.CLEAR_SCREEN)
+				printMap(sensors, max, max, h.Coordinate{X: tstX, Y: tstY})
+				fmt.Println("Testing", tstX, ",", tstY)
+				time.Sleep(time.Second / 10)
+				if testSpot(tstX, tstY, sensors) {
+					found = append(found, h.Coordinate{X: tstX, Y: tstY})
+				}
 			}
-			fmt.Println("Nope")
 		}
 	}
+
 	fmt.Println("# Part 2")
 	fmt.Println(found)
-	fmt.Println((found.X * 4000000) + found.Y)
+	//fmt.Println((found.X * 4000000) + found.Y)
 }
 
-func printMap(m [][]int) {
+func testSpot(x, y int, sensors []Sensor) bool {
+	var wasInRange bool
+	for i := range sensors {
+		if sensors[i].isInRange(h.Coordinate{X: x, Y: y}) {
+			wasInRange = true
+			break
+		}
+	}
+	return !wasInRange
+}
+
+func printMap(sensors []Sensor, ceilX, ceilY int, tstPos h.Coordinate) {
+	minX, maxX, minY, maxY := math.MaxInt, math.MinInt, math.MaxInt, math.MinInt
+	for i := range sensors {
+		minX = h.Min(sensors[i].b.X, minX)
+		maxX = h.Max(sensors[i].b.X, maxX)
+		minY = h.Min(sensors[i].b.Y, minY)
+		maxY = h.Max(sensors[i].b.Y, maxY)
+	}
+	for y := minY; y <= maxY; y++ {
+		for x := minX; x <= maxX; x++ {
+			wrk := h.Coordinate{X: x, Y: y}
+			var found bool
+			for _, sensor := range sensors {
+				if sensor.c.Equals(wrk) {
+					fmt.Print("S")
+					found = true
+					break
+				} else if sensor.b.Equals(wrk) {
+					fmt.Print("B")
+					found = true
+					break
+				} else if sensor.isInRange(wrk) {
+					fmt.Print("#")
+					found = true
+					break
+				}
+			}
+			if !found {
+				if wrk.Equals(tstPos) {
+					fmt.Print(h.FILL_CHAR)
+				} else {
+					fmt.Print(".")
+				}
+			}
+		}
+		fmt.Println()
+	}
 }
 
 func strToCoords(s string) (h.Coordinate, h.Coordinate) {