move steps into tracker... it is afterall, the tracker

initializeTracker should be a factory function

day-10/one.go

@@ -28,6 +28,25 @@ type tracker struct {
 	init  point
 	point point
 	last  []coords
+	steps int
+}
+
+// newTracker stores the starting point
+// it creates a queue for storing past 2 moves
+// returns a tracker struct for counting steps
+func newTracker() tracker {
+	tracker := tracker{last: make([]coords, 0)}
+	for _, each := range pointsArray {
+		for _, point := range each.points {
+			if point.identifier == 'S' {
+				tracker.init = point
+				tracker.point = tracker.init
+				tracker.last = make([]coords, 1)
+				tracker.last = append(tracker.last, tracker.point.coords)
+			}
+		}
+	}
+	return tracker
 }
 
 func (t tracker) X() int {
@@ -73,28 +92,11 @@ func mapPoints(lines []string) {
 	}
 }
 
-// initializeTracker stores the starting point, creates coords array for tracking last moves
-func initializeTracker() tracker {
-	tracker := tracker{last: make([]coords, 0)}
-	for _, each := range pointsArray {
-		for _, point := range each.points {
-			if point.identifier == 'S' {
-				tracker.init = point
-				tracker.point = tracker.init
-				tracker.last = make([]coords, 1)
-				tracker.last = append(tracker.last, tracker.point.coords)
-			}
-		}
-	}
-	return tracker
-}
-
 // walk moves along the pipes storing poinst that mark loop locations
 // it also keeps a track of last two moves
 // returns the number of steps to traverse all pipes
 func walk(tracker tracker) int {
-	var steps int
+	for ; tracker.steps == 0 || !comparePoints(tracker.init, tracker.point); tracker.steps++ {
-	for steps := 0; steps == 0 || !comparePoints(tracker.init, tracker.point); steps++ {
 		next := checkSouth(tracker.point)
 		if !inLastMoves(tracker.last, next.coords) {
 			log.Debug("moving south from ", string(tracker.point.identifier), " to ", string(next.identifier))
@@ -127,16 +129,16 @@ func walk(tracker tracker) int {
 			tracker.last = append(tracker.last[1:], next.coords)
 			continue
 		}
-		steps++
+		tracker.steps++ // the very last move will be back at start
 	}
-	return steps
+	return tracker.steps
 }
 
 // one returns the number of steps to reach the furthest point from the start
 func one(lines []string) int {
 	mapPoints(lines)
 
-	tracker := initializeTracker()
+	tracker := newTracker()
 
 	return walk(tracker) / 2
 }

day-10/two.go

@@ -22,7 +22,7 @@ func debugPrint() {
 
 var loop []coords
 
-// two
+// two returns the number of coords that sit inside the polygon
 func two(lines []string) int {
 	if log.GetLevel() == log.DebugLevel {
 		debugPrint()