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diff --git a/2020/aoc2020-d18.py b/2020/aoc2020-d18.py
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+#advent of code 2020
+#day 18
+#in my first or second aoc I coded a function to find nested brackets
+#that was painful and Im not doing it again
+#therefore regex
+
+import re
+
+def calcAdvanced(equation): #part 2
+	while True:
+		try:
+			lb, ub = re.search(r'(\d)+\s{1}(\+){1}(\s){1}\d+', equation).span();
+			subequation = equation[lb:ub].split(" ");
+			equation = equation[0:lb] + str(calcOperators(subequation)) + equation[ub:];
+		except:
+			break;
+	return int(eval(equation));
+	
+def calcOperators(values): #part 1
+	prev = values[0];
+	for v in range(2,len(values),2):
+		prev = str(eval(prev+values[v-1]+values[v]));
+	return prev;
+
+def calcBrackets(eq,part):
+	while True:
+		try:
+			lb, ub = re.search(r'\({1}([\d]|[\s]|[*]|[+])+\){1}', eq).span();
+			if part == 1: 
+				subeq = eq[lb+1:ub-1].split(" ");
+				newval = str(calcOperators(subeq));
+			else:
+				subeq = eq[lb:ub];
+				newval = str(calcAdvanced(subeq));
+			eq = eq[0:lb] + newval + eq[ub:];
+		except:
+			break;
+	if part == 1:
+		subeq = eq.split(" ");
+		return int(calcOperators(subeq));
+	else: 
+		return int(calcAdvanced(eq));
+
+p1 = 0;
+p2 = 0;
+PuzzleInput = open("18.in","r");
+for line in PuzzleInput:
+	line = line[:-1];
+	p1 += calcBrackets(line,1);
+	p2 += calcBrackets(line,2);
+PuzzleInput.close();
+print("part 1 =",p1);
+print("part 2 =",p2);