day8 part1 solution

day8/part1/main.go

@@ -0,0 +1,71 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strings"
+)
+
+func main() {
+	pixelString := readInputFile("./input.txt")
+
+	// fmt.Println(pixelString)
+
+	charsSlice := strings.Split(pixelString, "")
+	// fmt.Println(charsSlice)
+
+	layers := make([][]string, 0)
+	// layers are 25x6
+	// there are multiple layers of the same size
+	for i := 0; i*150 < len(charsSlice); i++ {
+		layers = append(layers, charsSlice[150*i:150*(i+1)])
+	}
+	// fmt.Println(layers)
+
+	min, minIndex := 150, 0 // start at 150, max length of one of our nested arrays
+	for index, layerSlice := range layers {
+		countZeroes := 0
+		for _, pixel := range layerSlice {
+			if pixel == "0" {
+				countZeroes++
+			}
+		}
+		if countZeroes < min {
+			min = countZeroes
+			minIndex = index
+			// fmt.Println(min, minIndex)
+		}
+	}
+
+	ones, twos := 0, 0
+	// count ones and twos of the layer with the least zeroes
+	for _, pixel := range layers[minIndex] {
+		if pixel == "1" {
+			ones++
+		} else if pixel == "2" {
+			twos++
+		}
+	}
+
+	fmt.Println(ones * twos)
+}
+
+func readInputFile(path string) string {
+	var pixelString string
+
+	file, err := os.Open(path)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := scanner.Text()
+		pixelString = line
+	}
+
+	return pixelString
+}