summertime warmup session - finish

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diff --git a/2020/aoc2020-d23.py b/2020/aoc2020-d23.py
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+#advent of code 2020
+#day 23
+#kinda cheated, I used another guy's solution for debugging
+# https://0xdf.gitlab.io/adventofcode2020/23 (cool source btw)
+#turns out my dictionary was getting one value from input replaced 
+#which caused "cutting off" most of the other numbers 
+#also tried filling out the dictionary with all numbers
+#but I was getting confused by different indexation
+#puzzle uses (0,1mil] instead of "standard" [0,1mil)
+#also minor mistakes in substitution ordering
+PuzzleInput = open("23.in","r").read().replace("\n","");
+cups = [int(v) for v in PuzzleInput];
+
+def cupgame(cuplabels, lim, cuplim):
+	cupdict = dict();
+	for c_i in range(len(cuplabels) -1):
+		cupdict[cuplabels[c_i]] = cuplabels[c_i+1];
+	if cuplim == len(cuplabels):
+		cupdict[cuplabels[-1]] = cuplabels[0];
+	else:
+		cupdict[cuplabels[-1]] = 10;
+		for c_i in range(len(cuplabels)+1,cuplim):
+			cupdict[c_i] = c_i + 1;
+		cupdict[ cuplim ] = cuplabels[0];
+	
+	c0 = 0 + cuplabels[0];
+	for step in range(lim):
+		if step%1000000 == 0: print(step//1000000,"/",lim//1000000);
+		c1 = cupdict[c0] #,(c0+1)%(cuplim+1) +1);
+		c2 = cupdict[c1] #,(c1+1)%(cuplim+1) +1);
+		c3 = cupdict[c2] #,(c2+1)%(cuplim+1) +1);
+		cupdict[c0] = cupdict[c3] #,(c3+1)%(cuplim+1) +1);
+		d0 = c0 - 1;
+		if d0 == 0: d0 = cuplim;
+		while True:
+			if d0 not in [c1,c2,c3]: break;
+			d0 -= 1;
+			if d0 == 0: d0 = cuplim;
+		cupdict[c3] = cupdict[d0];
+		cupdict[d0] = c1;
+		c0 = cupdict[c0];
+		
+	if cuplim == len(cuplabels):
+		solution = "";
+		NextVal = 1;
+		for s in range(8):
+			NextVal = cupdict[NextVal];
+			solution += str(NextVal);
+	else:
+		solution = cupdict[1] * cupdict[cupdict[1]];
+		
+	return solution;
+
+p1 = cupgame(cups,100, len(cups));
+p2 = cupgame(cups,10000000, 1000000);
+print("part 1 =",p1);
+print("part 2 =",p2);
+