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+#advent of code 2020
+#day 12
+#Im experimenting with different parsing, 
+#the [:-1] is for skipping the empty line
+#big mistake: giving north a negative value, 
+#which meant that my left and right turns where flipped
+#changed it after getting the correct value
+navigationInstructions = [line for line in open("12.in","r").read().split("\n")][:-1];
+
+directions = dict();
+directions[0] = (0,1); #east
+directions[1] = (-1,0); #south
+directions[2] = (0,-1); #west
+directions[3] = (1,0); #north
+
+#part 1
+def actions(act,val,face):
+	if act == "N":
+		return (val,0,face);
+	elif act =="S":
+		return (-val,0,face);
+	elif act == "E":
+		return (0,val,face);
+	elif act == "W":
+		return (0,-val,face);
+	elif act == "L":
+		turn = val//90;
+		tempF = (4+face-turn)%4;
+		return (0,0,tempF);
+	elif act == "R":
+		turn = val//90;
+		tempF = (4+face+turn)%4
+		return (0,0,tempF);
+	elif act == "F":
+		mody,modx = directions[face];
+		return (mody*val,modx*val,face);
+
+#part 2
+def NewActions(act,val,wayY,wayX):
+	if act == "N":
+		return (0,0,wayY+val,wayX);
+	elif act =="S":
+		return (0,0,wayY-val,wayX);
+	elif act == "E":
+		return (0,0,wayY,wayX+val);
+	elif act == "W":
+		return (0,0,wayY,wayX-val);
+	elif act == "L":
+		turn = val//90;
+		tempW = (wayY,wayX);
+		for t in range(turn):
+			tempW = (tempW[1],-tempW[0]);
+		return (0,0,tempW[0],tempW[1]);
+	elif act == "R":
+		turn = val//90;
+		tempW = (wayY,wayX);
+		for t in range(turn):
+			tempW = (-tempW[1],tempW[0]);
+		return (0,0,tempW[0],tempW[1]);
+	elif act == "F":
+		return (wayY*val,wayX*val,wayY,wayX);
+	else:
+		return False;
+	
+#ship coordinates, part 1
+X1 = 0; 
+Y1 = 0;
+D1 = 0; #direction
+#ship coordinates, part 2
+X2,Y2,D2 = 0,0,0;
+WX, WY = 10,1; #waypoint relative coordinates
+
+for instr in navigationInstructions:
+	action = instr[0];
+	value = int(instr[1:]);
+	dy1,dx1,dd1 = actions(action,value,D1); #part 1
+	Y1 += dy1;
+	X1 += dx1;
+	D1 = dd1;
+	dy2,dx2,dwy,dwx = NewActions(action,value,WY, WX); #part 2
+	Y2 += dy2;
+	X2 += dx2;
+	WY = dwy;
+	WX = dwx;
+
+if X1 < 0: X1 = -X1;
+if Y1 < 0: Y1 = -Y1;
+p1 = X1 + Y1;
+if X2 < 0: X2 = -X2;
+if Y2 < 0: Y2 = -Y2;
+p2 = X2 + Y2;
+print("part 1 =",p1);
+print("part 2 =",p2);