day2

2024/go/day02/day02.go

@@ -0,0 +1,105 @@
+package day02
+
+import (
+	"adventofcode2024/utils"
+	_ "adventofcode2024/utils"
+	_ "adventofcode2024/utils/grid2d"
+	_ "adventofcode2024/utils/inputs"
+	_ "errors"
+	_ "fmt"
+	"strings"
+)
+
+type Dir int
+
+const (
+    Up Dir = iota
+    Down
+    Safe
+	Unsafe
+)
+
+// Implement the Stringer interface
+func (d Dir) String() string {
+    switch d {
+    case Up:
+        return "Up"
+    case Down:
+        return "Down"
+    case Safe:
+        return "Safe"
+	case Unsafe:
+        return "Unsafe"
+	default:
+		return "Unknown"
+    }
+}
+
+func Part1(input string) int {
+	count := 0
+	lines := strings.Split(input, "\n")
+	for _, line := range lines {
+		fields := strings.Fields(line)
+		if isSafe(fields) {count++}
+	}
+	return count
+}
+
+func Part2(input string) int {
+	count := 0
+	lines := strings.Split(input, "\n")
+	for _, line := range lines {
+		fields := strings.Fields(line)
+		if isSafe(fields) {
+			count++
+		} else {
+			for i := 0; i < len(fields); i++ {
+				// Create a new slice excluding the current item
+				newFields := applyDampner(fields, i)
+				if isSafe(newFields) {
+					count++
+					break
+				}
+			}
+		}
+	}
+	return count
+}
+
+func isSafe(fields []string) bool {
+	Dir := getDir(utils.MustAtoi(fields[0]), utils.MustAtoi(fields[1]))
+	if Dir == Unsafe {
+			return false
+	}
+	for x := 2; x < len(fields); x++ {
+		NextDir := getDir(utils.MustAtoi(fields[x-1]), utils.MustAtoi(fields[x]))
+		if NextDir == Unsafe {
+			return false
+		}
+		if NextDir != Dir {
+			return false
+		}
+	}
+	return true
+}
+
+func getDir(a int, b int) Dir {
+	var dir Dir
+	diff := b - a
+	if diff > 0 && utils.Abs(diff) < 4 {
+		dir = Up
+	} else if diff < 0 && utils.Abs(diff) < 4 {
+		dir = Down
+	} else {
+		dir = Unsafe
+	}
+	return dir
+}
+
+func applyDampner(fields []string, pos int) []string {
+	copy := append([]string{}, fields...)
+    if pos < 0 || pos >= len(copy) {
+        return copy // Return the fields unchanged if pos is invalid
+    }
+    return append(copy[:pos], copy[pos+1:]...)
+}