day 22

22/22.2.go

@@ -0,0 +1,132 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+)
+
+// Coords are y,x as first grid array index = y coord.
+
+// cat input | go run 22.2.go
+
+func main() {
+
+	grid := make(map[string]int)
+
+	scanner := bufio.NewScanner(os.Stdin)
+
+	y := 0
+	for scanner.Scan() {
+		text := scanner.Text()
+		for x := range text {
+			coords := fmt.Sprint(x,y)
+			fmt.Println(coords)
+			if text[x] == '#' {
+				grid[coords] = 2
+			}
+		}
+		y++
+
+	}
+
+	posX := y/2
+	posY := y/2
+	dir := "u"
+	infections := 0
+
+	fmt.Println(grid)
+	fmt.Println(posX, posY, dir)
+
+	for i:=0; i<10000000; i++ {
+		current := fmt.Sprint(posX, posY)
+		node := grid[current]
+		// Turn
+		dir = Turn(dir, node)
+		// Infect/clean
+		result := ProcessNode(node)
+		grid[current] = result
+		if result == 2 {
+			infections++
+		}
+		// Move
+		posX, posY = Move(posX, posY, dir)
+	}
+	fmt.Println(infections)
+
+}
+
+func ProcessNode(node int) int {
+	// 0 clean
+	// 1 weakened
+	// 2 infected
+	// 3 flagged
+	if node == 3 {
+		node = 0
+	} else {
+		node++
+	}
+	return node
+}
+
+func Move (posX int, posY int, dir string) (int,int) {
+	switch dir {
+	case "u":
+		posY--
+	case "d":
+		posY++
+	case "l":
+		posX--
+	case "r":
+		posX++
+	}
+	return posX, posY
+}
+
+func Turn (dir string, state int) string {
+
+	// flagged
+	if state == 3 {
+		switch dir {
+		case "u":
+			return "d"
+		case "d":
+			return "u"
+		case "l":
+			return "r"
+		case "r":
+			return "l"
+		}
+	} 
+
+	// infected
+	if state == 2 {
+		switch dir {
+		case "u":
+			return "r"
+		case "d":
+			return "l"
+		case "l":
+			return "u"
+		case "r":
+			return "d"
+		}
+	} 
+ 
+	// clean (state 0)
+	if state == 0 {
+		switch dir {
+		case "u":
+			return "l"
+		case "d":
+			return "r"
+		case "l":
+			return "d"
+		case "r":
+			return "u"
+		}
+	}
+	
+	// weakened (state 1)
+	return dir
+}

22/22.go

@@ -0,0 +1,98 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+)
+
+// Coords are y,x as first grid array index = y coord.
+
+// cat input | go run 22.go
+
+func main() {
+
+	grid := make(map[string]int)
+
+	scanner := bufio.NewScanner(os.Stdin)
+
+	y := 0
+	for scanner.Scan() {
+		text := scanner.Text()
+		for x := range text {
+			coords := fmt.Sprint(x,y)
+			fmt.Println(coords)
+			if text[x] == '#' {
+				grid[coords] = 1
+			}
+		}
+		y++
+
+	}
+
+	posX := y/2
+	posY := y/2
+	dir := "u"
+	infections := 0
+
+	fmt.Println(grid)
+	fmt.Println(posX, posY, dir)
+
+	for i:=0; i<10000; i++ {
+		current := fmt.Sprint(posX, posY)
+		node := grid[current]
+		// Turn
+		dir = Turn(dir, node)
+		// Infect/clean
+		if node == 1 {
+			grid[current] = 0
+		} else {
+			grid[current] = 1
+			infections++
+		}
+		// Move
+		posX, posY = Move(posX, posY, dir)
+	}
+	fmt.Println(infections)
+
+}
+
+func Move (posX int, posY int, dir string) (int,int) {
+	switch dir {
+	case "u":
+		posY--
+	case "d":
+		posY++
+	case "l":
+		posX--
+	case "r":
+		posX++
+	}
+	return posX, posY
+}
+
+func Turn (dir string, infected int) string {
+	if infected == 1 {
+		switch dir {
+		case "u":
+			return "r"
+		case "d":
+			return "l"
+		case "l":
+			return "u"
+		case "r":
+			return "d"
+		}
+	} 
+	switch dir {
+	case "u":
+		return "l"
+	case "d":
+		return "r"
+	case "l":
+		return "d"
+	case "r":
+		return "u"
+	}
+	return ""
+}