Added solutions for 11th day: octopus flashes

2021/11/second.go

@@ -0,0 +1,63 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+)
+
+var (
+	grid  = make([][]byte, 0)
+	score = 0
+)
+
+func powerup(x, y int) {
+	if x < 0 || x > 9 || y < 0 || y > 9 || grid[x][y] > 9 {
+		return
+	}
+	grid[x][y]++
+	if grid[x][y] > 9 {
+		score++
+		powerup(x-1, y-1)
+		powerup(x, y-1)
+		powerup(x+1, y-1)
+		powerup(x-1, y)
+		powerup(x+1, y)
+		powerup(x-1, y+1)
+		powerup(x, y+1)
+		powerup(x+1, y+1)
+	}
+}
+func main() {
+	scanner := bufio.NewScanner(os.Stdin)
+	for scanner.Scan() {
+		line := scanner.Text()
+		l := make([]byte, len(line))
+		for i := 0; i < len(line); i++ {
+			l[i] = line[i] - '0'
+		}
+		grid = append(grid, l)
+	}
+
+	i := 0
+	for {
+		score = 0
+		for y := 0; y < 10; y++ {
+			for x := 0; x < 10; x++ {
+				powerup(x, y)
+			}
+		}
+		for y := 0; y < 10; y++ {
+			for x := 0; x < 10; x++ {
+				if grid[x][y] > 9 {
+					grid[x][y] = 0
+				}
+			}
+		}
+		i++
+		if score == 100 {
+			break
+		}
+	}
+	fmt.Println(i)
+}