package main import ( "bufio" "fmt" "log" "os" "strings" ) type Dig struct { direction string length int color string } func readInput(file *os.File) []Dig { scanner := bufio.NewScanner(file) var plan []Dig for scanner.Scan() { line := scanner.Text() if line == "" { break } var current Dig n, err := fmt.Sscanf(line, "%s %d %s", ¤t.direction, ¤t.length, ¤t.color) if n != 3 || err != nil { log.Fatalf("Wrong input: %s\n%s", line, err) } current.color = strings.Trim(current.color, "()") plan = append(plan, current) } return plan } type Point struct { y, x int } const ( Up = "U" Down = "D" Left = "L" Right = "R" ) func (p *Point) getPoints(dig Dig) []Point { var points []Point for i := 0; i < dig.length; i++ { switch dig.direction { case Up: p.y-- case Down: p.y++ case Left: p.x-- case Right: p.x++ } points = append(points, *p) } return points } func plot(plan []Dig) []Point { var current Point result := []Point{current} for i := range plan { result = append(result, current.getPoints(plan[i])...) } return result } func main() { if len(os.Args) < 2 { log.Fatal("You need to specify a file!") } filePath := os.Args[1] file, err := os.Open(filePath) if err != nil { log.Fatalf("Failed to open %s!\n", filePath) } plan := readInput(file) fmt.Println(plot(plan)) }