AoC, Day 2, Part 1 (Solved)

2023/02/code.go

@@ -0,0 +1,80 @@
+package main
+
+import (
+	"regexp"
+	"strconv"
+	"strings"
+
+	"github.com/jpillora/puzzler/harness/aoc"
+)
+
+func main() {
+	aoc.Harness(run)
+}
+
+// on code change, run will be executed 4 times:
+// 1. with: false (part1), and example input
+// 2. with: true (part2), and example input
+// 3. with: false (part1), and user input
+// 4. with: true (part2), and user input
+// the return value of each run is printed to stdout
+func run(part2 bool, input string) any {
+	// when you're ready to do part 2, remove this "not implemented" block
+	if part2 {
+		return "not implemented"
+	}
+	// solve part 1 here
+
+	redMax := 12
+	greenMax := 13
+	blueMax := 14
+	sum := 0
+
+	gameIdRxp := regexp.MustCompile(`Game (?P<ID>\d+):(?P<Data>.*)`)
+
+	for _, line := range strings.Split(input, "\n") {
+
+		matches := gameIdRxp.FindStringSubmatch(line)
+		if len(matches) == 0 {
+			continue
+		}
+
+		id, _ := strconv.Atoi(matches[1])
+		data := matches[2]
+
+		valid := true
+	drawLoop:
+		for _, draw := range strings.Split(data, ";") {
+			redDraw := 0
+			greenDraw := 0
+			blueDraw := 0
+
+			for _, single := range strings.Split(strings.Trim(draw, " "), ",") {
+				split := strings.Split(strings.Trim(single, " "), " ")
+
+				count, _ := strconv.Atoi(strings.Trim(split[0], " "))
+				colour := split[1]
+
+				if colour == "red" {
+					redDraw += count
+				} else if colour == "blue" {
+					blueDraw += count
+				} else if colour == "green" {
+					greenDraw += count
+				}
+
+				if redDraw > redMax || blueDraw > blueMax || greenDraw > greenMax {
+					valid = false
+					break drawLoop
+				}
+			}
+		}
+
+		if valid {
+			sum += id
+		}
+
+	}
+
+	return sum
+}