summertime warmup session - finish

1 files changed, 74 insertions, 0 deletions

diff --git a/2020/aoc2020-d22.py b/2020/aoc2020-d22.py
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+#advent of code 2020
+#day 22
+#some problems with copying, modifying, accessing data between functions
+#had a bit of workarounds
+#Im too lazy to reduce the amount of code 
+#by including part1 and part2 in a single function
+
+def NormalCombat(player1, player2):
+	decks = dict();
+	decks[0] = player1.copy();
+	decks[1] = player2.copy(); 
+	while len(decks[0]) > 0 and len(decks[1]) > 0 :
+		card0 = decks[0].pop(0);
+		card1 = decks[1].pop(0);		
+		if card0 > card1:
+			decks[0].append(card0);
+			decks[0].append(card1);
+		elif card0 < card1:
+			decks[1].append(card1);
+			decks[1].append(card0);
+	score = 0;
+	for deck in decks:
+		if len(decks[deck]) == 0: continue;
+		for c, card in enumerate(decks[deck]):
+			score += (len(decks[deck])-c)*card
+		break;
+	return score;
+
+def RecursiveCombat(player1, player2):
+	decks = dict();
+	decks[0] = player1.copy();
+	decks[1] = player2.copy(); 
+	previoushands = dict();
+	previoushands[0] = [];
+	previoushands[1] = [];
+	while len(decks[0]) > 0 and len(decks[1]) > 0 :
+		if tuple(decks[0]) in previoushands[0] and tuple(decks[1]) in previoushands[1]:
+			return 0, None;
+		previoushands[0].append(tuple(decks[0]));
+		previoushands[1].append(tuple(decks[1]));
+		card0 = decks[0].pop(0);
+		card1 = decks[1].pop(0);
+		if card0 <= len(decks[0]) and card1 <= len(decks[1]):
+			winner, winscore = RecursiveCombat(decks[0][:card0],decks[1][:card1]);
+		elif card0 > card1:
+			winner = 0;
+		elif card0 < card1:
+			winner = 1;
+		playedcards = [card0,card1];
+		decks[winner].append(playedcards[winner]);
+		decks[winner].append(playedcards[(winner+1)%2]);
+	score = 0;
+	for deck in decks:
+		#print(decks[deck]);
+		if len(decks[deck]) == 0: continue;
+		for c, card in enumerate(decks[deck]):
+			score += (len(decks[deck])-c)*card
+		winplayer = 0 + deck;
+		break;
+	return winplayer, score;
+
+PuzzleInput = open("22.in","r").read();
+playerdata1, playerdata2 = PuzzleInput.split("\n\n");
+playerdecks = dict();
+for pi, playerdata in enumerate( [playerdata1,playerdata2] ):
+	playerdecks[pi] = [int(val) for val in playerdata.split("\n")[1:] if val != ""];
+
+p1 = NormalCombat(playerdecks[0],playerdecks[1]);
+print("part 1 =",p1);
+_, p2 = RecursiveCombat(playerdecks[0],playerdecks[1]);
+print("part 2 =",p2);
+print('''part 1 = 34664
+part 2 = 32018
+''');