day14 go

1 files changed, 105 insertions, 0 deletions

diff --git a/2022/day14.go b/2022/day14.go
new file mode 100644
index 0000000..274ff95
--- /dev/null
+++ b/2022/day14.go
@@ -0,0 +1,105 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func min(x, y int) int {
+	if x < y {
+		return x
+	}
+	return y
+}
+
+func max(x, y int) int {
+	if x > y {
+		return x
+	}
+	return y
+}
+
+func add_sand(g map[[2]int]int, part int, max_y int, y int, x int) map[[2]int]int {
+	if part == 1 && y > max_y {
+		return g
+	} else if part == 2 && (y == (max_y + 1)) {
+		g[[2]int{y, x}] = 1
+		return g
+	} else if _, exists := g[[2]int{y + 1, x}]; !exists {
+		return add_sand(g, part, max_y, y+1, x)
+	} else if _, exists := g[[2]int{y + 1, x - 1}]; !exists {
+		return add_sand(g, part, max_y, y+1, x-1)
+	} else if _, exists := g[[2]int{y + 1, x + 1}]; !exists {
+		return add_sand(g, part, max_y, y+1, x+1)
+	} else {
+		g[[2]int{y, x}] = 1
+		return g
+	}
+}
+
+func main() {
+	// filename := "in/day14.ref"
+	filename := "in/day14.pzl"
+	file, err := os.Open(filename)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	g := map[[2]int]int{}
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := scanner.Text()
+		path := strings.Split(line, " -> ")
+
+		xy := strings.Split(path[0], ",")
+		xs, _ := strconv.Atoi(xy[0])
+		ys, _ := strconv.Atoi(xy[1])
+		for i := 1; i < len(path); i++ {
+			xy = strings.Split(path[i], ",")
+			xe, _ := strconv.Atoi(xy[0])
+			ye, _ := strconv.Atoi(xy[1])
+			for x := min(xs, xe); x < max(xs, xe)+1; x++ {
+				for y := min(ys, ye); y < max(ys, ye)+1; y++ {
+					g[[...]int{y, x}] = 1
+				}
+			}
+			xs = xe
+			ys = ye
+		}
+	}
+	if err := scanner.Err(); err != nil {
+		log.Fatal(err)
+	}
+
+	// fmt.Println(g)
+	// fmt.Println(len(g))
+	var max_y int = 0
+	for key, _ := range g {
+		if key[0] > max_y {
+			max_y = key[0]
+		}
+	}
+	// fmt.Println("max_y:", max_y)
+
+	for _, part := range []int{1, 2} {
+		gdup := map[[2]int]int{}
+		for k, v := range g {
+			gdup[k] = v
+		}
+		var start_len int = len(gdup)
+		for {
+			var prev_len int = len(gdup)
+			gdup = add_sand(gdup, part, max_y, 0, 500)
+			if prev_len == len(gdup) {
+				break
+			}
+		}
+		fmt.Println(len(gdup) - start_len)
+	}
+}