day21: yuck

day21/notes.org

@@ -9,3 +9,12 @@ but i could be doing loop around that would increase path len by odd number
 
 let's just make direct recursive thing.
 create set of all reachable by n,
+* oh, the part 2.
+i suppose this 'infinite' garden could be managed with my 'neighbors' work with 'out of field'
+fairly easy
+but what about sizes of the maps? are we releasing maps of previous iterations?
+
+maybe if i directly pass references to prev and current,
+and manually set 'prev' to target new it will be collected?
+
+and then elements after these steps <em>26501365</em> would fit into memory?

day21/stepCounter.go

@@ -9,7 +9,7 @@ import (
 
 func Run() int {
 	fmt.Print("hello day21")
-	filename := "day21/input"
+	filename := "day21/example"
 	field := ReadField(filename)
 	log.Print(field)
 
@@ -19,7 +19,6 @@ func Run() int {
 
 	fmt.Println(field.PrintCoord(reachableBySixtyFour))
 
-
 	return len(reachableBySixtyFour)
 }
 
@@ -37,8 +36,7 @@ type Coord struct {
 	Row, Col int
 }
 
-
-func (f Field)ReachableBySteps(n int, startingAt map[Coord]any) map[Coord]any {
+func (f Field) ReachableBySteps(n int, startingAt map[Coord]any) map[Coord]any {
 	if n == 0 {
 		return startingAt
 	}
@@ -54,7 +52,6 @@ func (f Field)ReachableBySteps(n int, startingAt map[Coord]any) map[Coord]any {
 	return f.ReachableBySteps(n-1, oneStepExpanded)
 }
 
-
 func (f Field) Neighbors(c Coord) (resut []Coord) {
 	closeCoords := []Coord{
 		{Row: c.Row + 1, Col: c.Col},
@@ -64,11 +61,13 @@ func (f Field) Neighbors(c Coord) (resut []Coord) {
 	}
 
 	for _, close := range closeCoords {
-		symb := f.symbols[close.Row][close.Col]
-		validNextPlace := f.ValidCoord(close.Row, close.Col) &&
-			(symb == '.' || symb == 'S')
-		if validNextPlace {
-			resut = append(resut, close)
+		if f.ValidCoord(close.Row, close.Col) {
+			symb := f.symbols[close.Row][close.Col]
+			if symb == '.' || symb == 'S' {
+				resut = append(resut, close)
+
+			}
+
 		}
 	}
 
@@ -114,7 +113,7 @@ func ReadField(filename string) (result Field) {
 	return
 }
 
-func (f Field)PrintCoord(coords map[Coord]any) string {
+func (f Field) PrintCoord(coords map[Coord]any) string {
 	result := ""
 	for rowNum, row := range f.symbols {
 		for colNum, col := range row {