Solve day03

day01.py

@@ -0,0 +1,22 @@
+def calc_inc(x):
+    prev = 0
+    count = 0
+    for i in x:
+        if i > prev and prev != 0:
+            count += 1
+        prev = i
+    return count
+
+
+with open("day01.in", "r") as f:
+    fa = [int(i.rstrip()) for i in f]
+    count_a = calc_inc(fa)
+
+    win = []
+    for i in range(len(fa)):
+        if i + 2 < len(fa):
+            win.append(sum(fa[i:i+3]))
+    count_b = calc_inc(win)
+
+print("Increased", count_a, "times")
+print("Increased", count_b, "times")

day02.py

@@ -0,0 +1,29 @@
+pos = [0, 0]
+direction_key = {"forward": (1, 0), "down": (0, 1), "up": (0, -1)}
+with open("day02.in") as f:
+    # fa = [i for i in f]
+    for x in f:
+        cmd = x.split()[0]
+        val = int(x.split()[1])
+        pos[0] += direction_key[cmd][0] * val
+        pos[1] += direction_key[cmd][1] * val
+
+print("Current position:", pos)
+print("Product:", pos[0] * pos[1])
+
+# Part 2
+pos = [0, 0, 0]
+with open("day02.in2") as f:
+    for x in f:
+        cmd = x.split()[0]
+        val = int(x.split()[1])
+        if cmd == "down":
+            pos[2] += val
+        elif cmd == "up":
+            pos[2] -= val
+        elif cmd == "forward":
+            pos[0] += val
+            pos[1] += pos[2] * val
+
+print("Current position:", pos)
+print("Product:", pos[0] * pos[1])

day03.py

@@ -0,0 +1,58 @@
+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()