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diff --git a/2024/aoc2024-d11.py b/2024/aoc2024-d11.py
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+#advent of code 2024
+#day 11
+#I liked it. what I did was:
+#store current stones in dictionary in format stonenumber:amount of these stones
+#iterate the changes in time
+#if the given stone is split up for the first time, the result is memorized
+#in the changes dictionary
+#during iteration, the UpdateStones function tries to read the results of splitting
+#if there are none, the stone is getting split up for the first time
+#repeat for given steps
+stones = {};
+changes = {};
+f = open("11.in","r");
+for s in f.readline().strip().split(" "):
+	si = int(s);
+	if si not in stones: stones[si] = 0;
+	stones[si] += 1;
+f.close();
+
+def SplitStones(stone):
+	NewStones = [];
+	if stone == 0:
+		NewStones.append(1);
+	elif len(str(stone))%2==0:
+		stonestring = str(stone);
+		sm = len(stonestring)//2;
+		s1,s2 = stonestring[0:sm], stonestring[sm:];
+		NewStones.append(int(s1));
+		NewStones.append(int(s2));
+	else:
+		NewStones.append(stone*2024);
+	return NewStones;
+
+def UpdateStones(prevStones):
+	Updated = {};
+	for s in prevStones:
+		if s not in changes: changes[s] = SplitStones(s);
+		for c in changes[s]:
+			if c not in Updated: Updated[c] = 0;
+			Updated[c] += prevStones[s];
+	return Updated;
+
+steps1 = 25; #for part 1
+steps2 = 75; #for part 2
+for step in range(1,steps2+1):
+	stones = UpdateStones(stones);
+	if step == steps1: part1 = sum([stones[x] for x in stones]);
+part2 = sum([stones[x] for x in stones]);
+print("part 1 =", part1);
+print("part 2 =", part2);