updates

2025/go/day01/day01.go

@@ -20,46 +20,45 @@ type Instruction struct {
 	Steps int
 }
 
-func Part1(input string) int {
-	lines := strings.Split(input, "\n")
-	position := 50
-	code := 0
+func parseInput(input string) []Instruction {
 	Instructions := make([]Instruction, 0)
+	lines := strings.Split(input, "\n")
 	for _, line := range lines {
 		var steps int
 		var dir Dir
+		steps = utils.MustAtoi(line[1:])
 		switch line[0] {
 		case 'L':
-			steps = utils.MustAtoi(line[1:])
 			dir = Left
 		case 'R':
-			steps = utils.MustAtoi(line[1:])
 			dir = Right
 		default:
 			fmt.Println("Invalid direction")
 			continue
 		}
-		if steps > 100 {
-			steps = steps % 100
-		}
 		Instructions = append(Instructions, Instruction{Turn: dir, Steps: steps})
 	}
-	fmt.Print(Instructions)
+	return Instructions
+}
+
+func Part1(input string) int {
+
+	Instructions := parseInput(input)
+	position := 50
+	code := 0
+
 	for _, instr := range Instructions {
-		if instr.Turn == Left {
-			if position-instr.Steps < 0 {
-				position = 100 + (position - instr.Steps)
-			} else {
-				position -= instr.Steps
-			}
-		} else if instr.Turn == Right {
-			if position+instr.Steps >= 100 {
-				position = (position + instr.Steps) - 100
-			} else {
-				position += instr.Steps
-			}
+		switch instr.Turn {
+		case Left:
+			position -= instr.Steps % 100
+		case Right:
+			position += instr.Steps % 100
+		}
+		if position < 0 {
+			position += 100
+		} else if position > 99 {
+			position -= 100
 		}
-		fmt.Println("\n", instr.Turn, instr.Steps, "->", position)
 		if position == 0 {
 			code++
 		}
@@ -68,61 +67,34 @@ func Part1(input string) int {
 }
 
 func Part2(input string) int {
-	lines := strings.Split(input, "\n")
+	Instructions := parseInput(input)
 	position := 50
 	code := 0
-	Instructions := make([]Instruction, 0)
-	for _, line := range lines {
-		var steps int
-		var dir Dir
-		switch line[0] {
-		case 'L':
-			steps = utils.MustAtoi(line[1:])
-			dir = Left
-		case 'R':
-			steps = utils.MustAtoi(line[1:])
-			dir = Right
-		default:
-			fmt.Println("Invalid direction")
-			continue
-		}
-		Instructions = append(Instructions, Instruction{Turn: dir, Steps: steps})
-	}
-	fmt.Print(Instructions)
+	new_position := position
+
 	for _, instr := range Instructions {
-		if instr.Steps > 100 {
-			code = code + (instr.Steps / 100)
-			instr.Steps = instr.Steps % 100
+		switch instr.Turn {
+		case Left:
+			new_position = position - instr.Steps%100
+		case Right:
+			new_position = position + instr.Steps%100
 		}
-		if instr.Turn == Left {
-			if position-instr.Steps < 0 {
-				if position != 0 {
-					code++
-				}
-				position = 100 + (position - instr.Steps)
-				
-			} else {
-				position -= instr.Steps
-				if position == 0 {
-					code++
-				}
+		code += instr.Steps / 100
+		if new_position == 0 {
+			code++
+		}
+		if new_position < 0 {
+			new_position += 100
+			if position != 0 {
+				code++
 			}
-		} else if instr.Turn == Right {
-			if position+instr.Steps > 99 {
-				if position != 0 {
-					code++
-				}
-				position = (position + instr.Steps) - 100
-			} else {
-				position += instr.Steps
-				if position == 0 {
-					code++
-				}
+		} else if new_position > 99 {
+			new_position -= 100
+			if position != 0 {
+				code++
 			}
 		}
-
-		fmt.Println("\n", instr.Turn, instr.Steps, "->", position, "code:", code)
-
+		position = new_position
 	}
 	return code
 }