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+#advent of code 2018 
+#day 17
+#part 1 and part 2
+
+#for me this is one of the most time consuming puzzles for this year
+#I got too cocky because I remembered a similar puzzle during 2022 edition
+#unfortunately 2018 day 17 was more tricky
+#I made 3 attempts, each time starting from scratch 
+#first time I just scrambled something, but there was no way to calculate when to stop the algo
+#so the water was extremely overflowing 
+#for second attempt I wrote 2 functions, one for flowing downwards, second for spreading
+#I spent a whole day "improving" the spreading function so it behaves correctly, to no avail 
+#I figured out the logic of the puzzle, but I kept getting weird errors
+#such as water bursting through walls or flowing upwards  
+#I was adding more and more if-elses, but they weren't fixing these bugs:
+#they were merely delaying them - after filling in the water correctly, the bugs were popping up again
+#third and final attempt was successful - I already learned the logic of the algorithm,
+#I just needed to implement it in bug-free way
+#on the other hand, I managed to get a pretty good runtime.
+#Every now and then I was looking up a solution for clues from others
+#one of which Michael Fogleman, probably my most common resource for learning AoC 2018
+#while his code runs for almost a minute, mine just needs less than 0.05 secs
+#it's really funny to "outperform" (in a way) someone whom you were constantly consulting for help
+#one last thing I want to mention is that during the third attempt I kept getting wrong answer
+#since I was only off by 3 and at the end there are only 3 waterfalls connecting to lowest point, 
+#I was convinced that I was calculating the solution for wrong range
+#turns out I misunderstood the puzzle - you're supposed to calculate the amount of still 
+#and flowing water in range of highest wall point and the lowest wall point, 
+#while I kept calculating it in range from zero to lowest
+#at least this time part2 was a freebee 
+
+import time;
+
+f = open("input.txt",'r');
+Testing = False;
+#Testing = True; 
+if Testing:
+	f.close();
+	f = open("testinput.txt",'r');
+
+def parse_input(line):
+	line = line.replace("x=","");
+	line = line.replace("y=","");
+	line = line.replace("..",",");
+	line = "[" + line + "]";
+	cords = eval(line);
+	return cords; #line coordinates: [x, y1, y2] or [y, x1, x2]
+
+Xmax = 500; #rightmost X coordinate, just for printing the area
+Xmin = 500; #leftmost X coordinate, just for printing the area
+Ymax = 0; #lowest Y coordinate, needed for solution
+Ymin2 = 2000; #highest Y coordinate, needed for solution
+LinesX = [];
+LinesY = [];
+
+for l in f:
+	d = l[0]; #direction x or y
+	Cords = parse_input(l);
+	if d == "x":
+		Xmax = max(Cords[0], Xmax);
+		Xmin = min(Cords[0], Xmin);
+		Ymax = max(Cords[2], Ymax);
+		Ymin2 = min(Cords[1], Ymin2);
+		LinesX.append(Cords);
+	else:
+		Xmax = max(Cords[2], Xmax);
+		Xmin = min(Cords[1], Xmin);
+		Ymax = max(Cords[0], Ymax);
+		Ymin2 = min(Cords[0], Ymin2);
+		LinesY.append(Cords);
+
+Xmax += 1;
+Xmin -= 1;
+Ymin = 0; 
+
+area = {};
+#initialize input into the area
+for l in LinesX:
+	x = l[0];
+	for y in range(l[1],l[2]+1):
+		area.update({(x,y):"#"});
+for l in LinesY:
+	y = l[0];
+	for x in range(l[1],l[2]+1):
+		area.update({(x,y):"#"});
+
+def wspread(cords, q):
+	r1 = 0;
+	r2 = 0;
+	x,y = cords;
+	while (area.get((x,y+1)," ") == "#" or area.get((x,y+1)," ") == "=") and area.get((x-1,y)," ") != "#":
+		r1 += 1;
+		x -= 1;
+	
+	x,y = cords;	
+	while (area.get((x,y+1)," ") == "#" or area.get((x,y+1)," ") == "=") and area.get((x+1,y)," ") != "#":
+		r2 += 1;
+		x += 1;
+	
+	x,y = cords;
+	if area.get((x-r1-1,y)," ") == "#" and area.get((x+r2+1,y)," ") == "#":
+		for r in range(x-r1,x+r2+1):
+			area[(r,y)] = "=";
+		q.append((cords[0],cords[1]-1));
+	else:
+		for r in range(x-r1,x+r2+1):
+			area[(r,y)] = "|";
+		if area[(x-r1,y)] != "#" and area.get((x-r1,y+1)," ") == " ":
+			q.append((x-r1,y));
+		if area[(x+r2,y)] != "#" and area.get((x+r2,y+1)," ") == " ":
+			q.append((x+r2,y));
+				
+def wfall(cords, q):
+	x,y = cords;
+	while area.get((x,y+1)," ")==" " and y < Ymax:
+		area[(x,y+1)] = "|";
+		y += 1;
+	if area.get((x,y)," ")=="#" or area.get((x,y)," ")=="=":
+		q.append((x,y-1));
+	elif y < Ymax:
+		q.append((x,y));
+
+t1 = time.time();
+water = [(500,0)];
+area.update({(500,0):"|"});
+
+while water:
+	w = water.pop();
+	if area.get((w[0],w[1]+1)," ")==" ":
+		wfall(w, water);
+	else:	
+		wspread(w, water);
+
+part1 = 0; 
+part2 = 0;
+for a in area:
+	part1 += 1*(area[a]=="|" or area[a]=="=")*(a[1] >= Ymin2);
+	part2 += 1*(area[a]=="=");
+
+t2 = time.time();
+
+print("part1 = ", part1);
+print("part2 = ", part2);
+print("runtime ", t2-t1);