refactor: add calculateSeatID helper to simplify code

2020/day05/main.go

@@ -15,9 +15,10 @@ func parseInput(file string) []string {
 	return strings.Split(string(content), "\n")
 }
 
-func PartOne(input []string) int {
-	maxSeatID := 0
-	for _, pass := range input {
+func calculateSeatID(pass string) int {
+	if len(pass) < 10 {
+		return -1
+	}
 	rowStr := pass[:7]
 	columnStr := pass[7:10]
 
@@ -35,7 +36,13 @@ func PartOne(input []string) int {
 		}
 	}
 
-		seatID := row*8 + column
+	return row*8 + column
+}
+
+func PartOne(input []string) int {
+	maxSeatID := 0
+	for _, pass := range input {
+		seatID := calculateSeatID(pass)
 		if seatID > maxSeatID {
 			maxSeatID = seatID
 		}