refactor: day 9 cleanup

Author: nikolay

9/main.go

@@ -8,7 +8,11 @@ func (pos Position) Move(dx, dy int) Position {
 	return Position{pos.x + dx, pos.y + dy}
 }
 
-func (pos Position) Distance(p Position) Position {
+func (pos Position) Add(p Position) Position {
+	return Position{pos.x + p.x, pos.y + p.y}
+}
+
+func (pos Position) Subtract(p Position) Position {
 	return Position{pos.x - p.x, pos.y - p.y}
 }
 
@@ -29,7 +33,7 @@ func Sign(x int) int {
 	return 0
 }
 
-func DirDelta(dir string) Position {
+func DirPosition(dir string) Position {
 	switch dir {
 	case "L":
 		return Position{-1, 0}

9/part1.go

@@ -26,10 +26,10 @@ func part1() {
 			continue
 		}
 		fields := strings.Fields(line)
-		delta := DirDelta(fields[0])
+		delta := DirPosition(fields[0])
 		for steps, _ := strconv.Atoi(fields[1]); steps > 0; steps-- {
-			head = head.Move(delta.x, delta.y)
-			dist := head.Distance(tail)
+			head = head.Add(delta)
+			dist := head.Subtract(tail)
 			if Abs(dist.x) > 1 || Abs(dist.y) > 1 {
 				tail = tail.Move(Sign(dist.x), Sign(dist.y))
 				positions[fmt.Sprintf("%v,%v", tail.x, tail.y)] = true

9/part2.go

@@ -27,11 +27,11 @@ func part2() {
 			continue
 		}
 		fields := strings.Fields(line)
-		delta := DirDelta(fields[0])
+		delta := DirPosition(fields[0])
 		for steps, _ := strconv.Atoi(fields[1]); steps > 0; steps-- {
-			ropes[0] = ropes[0].Move(delta.x, delta.y)
+			ropes[0] = ropes[0].Add(delta)
 			for r := 1; r < TailSize; r++ {
-				dist := ropes[r-1].Distance(ropes[r])
+				dist := ropes[r-1].Subtract(ropes[r])
 				if Abs(dist.x) > 1 || Abs(dist.y) > 1 {
 					ropes[r] = ropes[r].Move(Sign(dist.x), Sign(dist.y))
 					if r == TailSize-1 {

README.md

@@ -1,2 +1,5 @@
-# advent-of-code-2022
-Advent of Code (2022)
+# Advent of Code (2022)
+
+This repository has my solutions for this year's Advent of Code contest. They may not be pretty or optimal, but although it's hard to beat Python in expressiveness and brevity, I still try to solve the problems as fast as I can in Go.
+
+I only do minor code cleanup after obtaining the stars for the day and do not change the algorithm, regardless of how embarrassing it could be!