#advent of code 2018
#day 05
#part 1 and 2

#extremely slow, rewrite candidate

def polymer_d(a,b):
	return (cdiff == abs(ord(a) - ord(b)));

def polymer_strip(inp):
	is_poly = True;
	while is_poly:
		is_poly = False;
		for x in range(1,len(inp)):
			x1 = inp[x-1];
			x2 = inp[x];
			if polymer_d(x1,x2):
				#print((x1+x2));
				inp = inp.replace((x1+x2),"");
				#myinput = myinput[
				is_poly = True;
				break;
	return inp;

#part1
def PolymerReaction(myinput):
	is_poly = True;
	while is_poly:
		is_poly = False;
		sub = "";
		for x in range(2,len(myinput)):
			x1 = myinput[x-2];
			x2 = myinput[x-1];
			if polymer_d(x1,x2):
				myinput = sub + myinput[x:];
				is_poly = True;
				break;
			else:
				sub += x1;
	return len(myinput);

#part 2
def ShortestPolymer(myinput):
	inp_max = 999999;
	inp_c = "";
	for c in range(ord("A"),ord("Z")+1,1):
		subinput = myinput;
		subinput = subinput.replace(chr(c),"");
		subinput = subinput.replace(chr(c+cdiff),"");
		subinput = polymer_strip(subinput);
		if (len(subinput) < inp_max):
			inp_max = len(subinput);
			inp_c = c;
	return inp_max

f = open("05.in","r");
cdiff = 32;
PuzzleInput = f.read().replace("\n","");
f.close();
p1 = PolymerReaction(""+PuzzleInput);
print("part 1", p1);
p2 = ShortestPolymer(""+PuzzleInput);
print("part 2 ",p2);