Solve 2020/2/first

2020/2/first/go.mod

@@ -0,0 +1,3 @@
+module 2
+
+go 1.15

2020/2/first/main.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"strconv"
+	"strings"
+)
+
+func main() {
+
+	result := 0
+
+	data, err := ioutil.ReadFile("input.txt")
+	if err != nil {
+		fmt.Println("File reading error", err)
+		return
+	}
+	lines := strings.Split(string(data), "\n")
+
+	for _, line := range lines {
+		components := strings.FieldsFunc(string(line), split)
+		min, _ := strconv.Atoi(components[0])
+		max, _ := strconv.Atoi(components[1])
+		target := components[2]
+		password := components[3]
+
+		matches := 0
+
+		for _, letter := range strings.Split(password, "") {
+			if letter == target {
+				matches++
+			}
+		}
+
+		if matches >= min && matches <= max {
+			result++
+		}
+
+		matches = 0
+	}
+
+	fmt.Println(result)
+
+}
+
+func split(r rune) bool {
+	return r == '-' || r == ' ' || r == ':'
+}