Solve day03

day03.py

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+def common_bit(list, bit, invert=False):
+    bit_count = [0, 0]  # count of 0s and 1s respectively
+    for x in list:
+        if x[bit] == "0":
+            bit_count[0] += 1
+        elif x[bit] == "1":
+            bit_count[1] += 1
+    if bit_count[0] <= bit_count[1]:
+        return 0 if invert else 1
+    else:
+        return 1 if invert else 0
+
+
+def part1():
+    with open("day03.in", "r") as f:
+        fa = [line.rstrip() for line in f]
+        gamma = ""
+        epsilon = ""
+        for bit in range(len(fa[0])):
+            gamma += str(common_bit(fa, bit))
+            epsilon += str(common_bit(fa, bit, invert=True))
+        gamma_i = int(gamma, 2)
+        epsilon_i = int(epsilon, 2)
+        print("Gamma:", gamma_i)
+        print("Epsilon:", epsilon_i)
+        print("Power consumption:", gamma_i * epsilon_i)
+
+
+def part2():
+    with open("day03.in2", "r") as f:
+        fa = [line.rstrip() for line in f]
+        fb = fa.copy()
+        for bit in range(len(fa[0])):
+            fa = [x for x in fa if x[bit] == str(common_bit(fa, bit))]
+            # Break to stop if we're already down to one result
+            if len(fa) == 1:
+                break
+        for bit in range(len(fb[0])):
+            fb = [x for x in fb if x[bit] == str(common_bit(fb, bit,
+                  invert=True))]
+            if len(fb) == 1:
+                break
+        oxygen = int(fa[0], 2)
+        co2 = int(fb[0], 2)
+    print("Oxygen:", oxygen)
+    print("CO2:", co2)
+    print("Life support rating:", oxygen * co2)
+
+
+def main():
+    print("=== PART 1 ===")
+    part1()
+    print("=== PART 2 ===")
+    part2()
+
+
+if __name__ == "__main__":
+    main()