🌅

solutions/day3/day3.go

@@ -0,0 +1,92 @@
+package day3
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+)
+
+func in_set(target rune, set []rune) bool {
+	for _, char := range set {
+		if char == target {
+			return true
+		}
+	}
+	return false
+}
+
+func priority(value rune) int {
+	var base_value int = 0
+
+	if value >= 'A' && value <= 'Z' {
+		base_value = int('A') - 27
+	}
+
+	if value >= 'a' && value <= 'z' {
+		base_value = int('a') - 1
+	}
+
+	return int(value) - base_value
+}
+
+func part1_addition(runes []rune) int {
+	var total int = 0
+
+	midpoint := len(runes) / 2
+	left_runes := runes[0:midpoint]
+	right_runes := runes[midpoint:]
+
+	for pos, char := range left_runes {
+		if !in_set(char, left_runes[0:pos]) {
+			if in_set(char, right_runes) {
+				total += priority(char)
+			}
+		}
+	}
+
+	return total
+}
+
+func score_badge(set1 []rune, set2 []rune, set3 []rune) int {
+	for pos, char := range set1 {
+		if !in_set(char, set1[0:pos]) {
+			if in_set(char, set2) && in_set(char, set3) {
+				return priority(char)
+			}
+		}
+	}
+	fmt.Println("PANIC: Couldn't find overlapping badge item")
+	return 0
+}
+
+func Run(filename string) {
+	file, err := os.Open(filename)
+
+	if err != nil {
+		fmt.Println("Error opening file:", err)
+		return
+	}
+
+	scanner := bufio.NewScanner(file)
+	scanner.Split(bufio.ScanLines)
+	var total_overlap int = 0
+	var total_badge int = 0
+	var grouping [][]rune = [][]rune{}
+
+	for scanner.Scan() {
+		line := scanner.Text()
+		runes := []rune(line)
+		total_overlap += part1_addition(runes)
+
+		grouping = append(grouping, runes)
+		if len(grouping) == 3 {
+			total_badge += score_badge(grouping[0], grouping[1], grouping[2])
+			grouping = [][]rune{}
+		}
+	}
+
+	file.Close()
+
+	fmt.Println("Total initial score is", total_overlap)
+	fmt.Println("Total badge score is", total_badge)
+}