From 7354aef1026dcdf1c4bcf302ebb784699cd320cf Mon Sep 17 00:00:00 2001
From: onyx-and-iris <code@onyxandiris.online>
Date: Tue, 7 Jan 2025 17:33:55 +0000
Subject: [PATCH] dfs explore functions return only bool

---
 day-15/internal/one/solve.go   | 16 ++++++++--------
 day-15/internal/two/explore.go |  6 +++---
 day-15/internal/two/solve.go   | 22 +++++++++++-----------
 3 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/day-15/internal/one/solve.go b/day-15/internal/one/solve.go
index df58174..4aac242 100644
--- a/day-15/internal/one/solve.go
+++ b/day-15/internal/one/solve.go
@@ -16,8 +16,8 @@ func Solve(buf []byte) (int, error) {
 	for _, dir := range dirs {
 		log.Debugf("about to explore '%s' direction from robot location %v", string(dir), graph.robot)
 
-		stack, ok := explore(graph, graph.robot, directions(dir), newStack())
-		if !ok {
+		stack := newStack()
+		if ok := explore(graph.robot, directions(dir), stack, graph); !ok {
 			log.Debug("path ends with '#', continuing...")
 			continue
 		}
@@ -39,19 +39,19 @@ func Solve(buf []byte) (int, error) {
 	return sum, nil
 }
 
-func explore(graph *graph, next point, direction direction, stack *stack) (*stack, bool) {
+func explore(next point, direction direction, stack *stack, g *graph) bool {
 	ns := neighbours(next)
 
-	log.Debug(string(graph.valueAt(ns[direction])))
+	log.Debug(string(g.valueAt(ns[direction])))
 
-	switch graph.valueAt(ns[direction]) {
+	switch g.valueAt(ns[direction]) {
 	case '#':
-		return nil, false
+		return false
 	case '.':
-		return stack, true
+		return true
 	case 'O':
 		stack.Push(ns[direction])
 	}
 
-	return explore(graph, ns[direction], direction, stack)
+	return explore(ns[direction], direction, stack, g)
 }
diff --git a/day-15/internal/two/explore.go b/day-15/internal/two/explore.go
index 83d21e5..49b0e28 100644
--- a/day-15/internal/two/explore.go
+++ b/day-15/internal/two/explore.go
@@ -6,16 +6,16 @@ import (
 	orderedmap "github.com/wk8/go-ordered-map/v2"
 )
 
-func exploreDFS(graph *graph, next point, dir direction, stack *stack) (*stack, bool) {
+func exploreDFS(graph *graph, next point, dir direction, stack *stack) bool {
 	ns := neighbours(next)
 
 	log.Debug(string(graph.valueAt(ns[dir])))
 
 	switch graph.valueAt(ns[dir]) {
 	case '#':
-		return nil, false
+		return false
 	case '.':
-		return stack, true
+		return true
 	case '[', ']':
 		stack.Push(ns[dir])
 	}
diff --git a/day-15/internal/two/solve.go b/day-15/internal/two/solve.go
index 57ba61d..03d2b6b 100644
--- a/day-15/internal/two/solve.go
+++ b/day-15/internal/two/solve.go
@@ -20,9 +20,9 @@ func Solve(buf []byte) (int, error) {
 
 		switch directions(dir) {
 		case N, S:
-			exploreNorthSouth(graph, directions(dir))
+			exploreNorthSouth(directions(dir), graph)
 		case W, E:
-			exploreWestEast(graph, directions(dir))
+			exploreWestEast(directions(dir), graph)
 		}
 
 		log.Debugf("\n%s\n", graph.String())
@@ -40,27 +40,27 @@ func Solve(buf []byte) (int, error) {
 	return sum, nil
 }
 
-func exploreWestEast(graph *graph, direction direction) {
-	stack, ok := exploreDFS(graph, graph.robot, direction, newStack())
-	if !ok {
+func exploreWestEast(direction direction, g *graph) {
+	stack := newStack()
+	if ok := exploreDFS(g, g.robot, direction, stack); !ok {
 		log.Debug("path ends with '#', continuing...")
 		return
 	}
 
 	for !stack.IsEmpty() {
 		point := stack.Pop().(point)
-		graph.updateBox(point, direction)
+		g.updateBox(point, direction)
 	}
-	graph.updateRobot(direction)
+	g.updateRobot(direction)
 }
 
-func exploreNorthSouth(graph *graph, direction direction) {
-	om, ok := exploreBFS(graph, direction)
+func exploreNorthSouth(direction direction, g *graph) {
+	om, ok := exploreBFS(g, direction)
 
 	if ok {
 		for pair := om.Newest(); pair != nil; pair = pair.Prev() {
-			graph.updateBox(pair.Key, direction)
+			g.updateBox(pair.Key, direction)
 		}
-		graph.updateRobot(direction)
+		g.updateRobot(direction)
 	}
 }