Day 3 completed (I left the debug code)

day3/common.py

@@ -0,0 +1,3 @@
+def parse(filename: str) -> str:
+    with open(filename) as f:
+        return f.read()

day3/part1.py

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+#!/usr/bin/env python
+import re
+
+from common import parse
+
+
+def solve(input: str) -> int:
+    regex = r"mul\((\d+),(\d+)\)"
+    muls = re.findall(regex, input)
+    return sum(map(lambda x: int(x[0]) * int(x[1]), muls))
+
+
+def main():
+    print(solve(parse("input")))
+
+
+if __name__ == "__main__":
+    main()

day3/part2.py

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+#!/usr/bin/env python
+import re
+
+from common import parse
+
+
+def solve(input: str, debug=False) -> int:
+    regex = r"(mul\((\d+),(\d+)\)|do\(\)|don't\(\))"
+    prog = re.findall(regex, input)
+    the_sum = 0
+    enabled = True
+    for inst in prog:
+        if debug:
+            print(inst[0], end=": ")
+        if enabled and inst[0].startswith("mul"):
+            if debug:
+                print("multiplying")
+            the_sum += int(inst[1]) * int(inst[2])
+        elif enabled and inst[0] == "don't()":
+            if debug:
+                print("disabling")
+            enabled = False
+        elif not enabled and inst[0] == "do()":
+            if debug:
+                print("enabling")
+            enabled = True
+        else:
+            if debug:
+                print("noop")
+    return the_sum
+
+
+def main():
+    print(solve(parse("input")))
+
+
+if __name__ == "__main__":
+    main()