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+#advent of code 2024
+#day 12
+#we needed area of the plot and its perimiter
+#we floodfill given plot and store the coordinates of the plants
+#then, on the borders, we register the coordinates of the plants
+#that are adjacent to our plot and the direction from which it was
+#registered during floodfill. the length of this set (perim) is the perimiter
+#then, for part 2, we group the points in perim set by their direction
+#(3rd parameter), then we sort each group based on the coordinate
+#that is changing, that is: if the fence was registered from the north,
+#then it is part of the north-facing fence, so we sort it by the x-axis
+#identical for southern and similar for east/west (y-axis)
+#iterate over every fence point, if the gap is greater 1 then increment
+#the amount of sides. I probably should make a drawing because 
+#I'll forget what it does in the future despite writing this comment
+grid = {};
+f = open("12.in","r");
+for y,l in enumerate(f):
+	for x,c in enumerate(l.strip()):
+		grid[(x,y)]=c;
+f.close();
+
+dirs = [(1,0),(0,1),(-1,0),(0,-1)];
+visited = set();
+
+def getAdjacent(pos,l):
+	adj = [];
+	vis = set();
+	xp, yp = pos;
+	for di,d in enumerate(dirs):
+		dx,dy = d;
+		if grid.get((xp+dx,yp+dy),".") == l:
+			adj.append((xp+dx,yp+dy));
+		else:
+			vis.add((xp+dx,yp+dy,di));
+	return adj, vis;
+
+def sides(perimiter):
+	SidesTotal = 0;
+	NumberOfSides = {};
+	PerimsGrouped = {};
+	for di in range(4):
+		NumberOfSides[di] = 0;
+		PerimsGrouped[di] = [m for m in perimiter if m[2]==di];
+		PerimsGrouped[di] = sorted(PerimsGrouped[di], key=lambda m: (m[di%2],m[(di+1)%2]));
+		if len(PerimsGrouped[di]) == 0: 
+			continue;
+		else:
+			NumberOfSides[di] += 1;
+		prevx,prevy,prevd = PerimsGrouped[di][0];
+		for PerPos in PerimsGrouped[di][1:]:
+			x,y,d = PerPos;
+			if not(abs(x-prevx)==di%2 and abs(y-prevy) ==(di+1)%2): 
+				NumberOfSides[di] += 1;
+			prevx,prevy,prevd = x,y,d;
+		SidesTotal += NumberOfSides[di];
+	return SidesTotal;
+
+def fill(startpos, letter):
+	queue = [startpos];
+	perim = set(); #add points that aren't part of the area but are adjacent
+	v = set(); #visited points, that is: the area
+	while queue:
+		px,py = queue.pop();
+		if (px,py) in v: continue;
+		visited.add((px,py));
+		v.add((px,py));
+		NextValid, NextBorders = getAdjacent((px,py),letter);
+		queue.extend(NextValid);
+		perim = perim.union(NextBorders);
+	return len(v), len(perim), sides(perim);
+
+part1 = 0;
+part2 = 0;
+for g in grid:
+	if g in visited:continue;
+	L = grid[g];
+	LandArea, LandPerim, LandSides = fill(g,L);
+	part1 += LandArea*LandPerim;
+	part2 += LandArea*LandSides;
+
+print("part 1 =", part1);
+print("part 2 =", part2);