day 3

3/a.py

@@ -0,0 +1,33 @@
+with open("input.txt") as f:
+    lines = [i.strip() for i in f.readlines()]
+
+
+def count_digits(ar):
+    zeros = [0] * len(ar[0])
+    ones = [0] * len(ar[0])
+
+    for row in ar:
+        for pos, c in enumerate(row.strip()):
+            (zeros if c == "0" else ones)[pos] += 1
+
+    return zeros, ones
+
+
+zeros, ones = count_digits(lines)
+
+
+print(zeros)
+print(ones)
+
+# lol
+gamma_bits = []
+epsi_bits = []
+
+for pos, zero in enumerate(zeros):
+    gamma_bits.append("1" if zero < ones[pos] else "0")
+    epsi_bits.append("1" if zero > ones[pos] else "0")
+
+gamma = int("".join(gamma_bits), 2)
+epsi = int("".join(epsi_bits), 2)
+
+print(gamma * epsi)

3/b.py

@@ -0,0 +1,56 @@
+with open("input.txt") as f:
+    og_lines = [i.strip() for i in f.readlines()]
+
+lines = og_lines[:]
+
+
+def count_digits(ar):
+    zeros = [0] * len(ar[0])
+    ones = [0] * len(ar[0])
+
+    for row in ar:
+        for pos, c in enumerate(row.strip()):
+            (zeros if c == "0" else ones)[pos] += 1
+
+    return zeros, ones
+
+
+def filter_by_digit(lines, position, value):
+    return [i for i in lines if i[position] == value]
+
+
+# oxy = most common
+# co2 = least common
+
+# oxy
+position = 0
+while len(lines) > 1:
+    zeros, ones = count_digits(lines)
+    zeros, ones = zeros[position], ones[position]
+
+    print(zeros, ones, "pos", position, "remaining lines", len(lines))
+    lines = filter_by_digit(lines, position, "1" if ones >= zeros else "0")
+
+    position += 1
+
+oxy = lines[0]
+
+
+lines = og_lines[:]
+
+# co0
+position = 0
+while len(lines) > 1:
+    zeros, ones = count_digits(lines)
+    zeros, ones = zeros[position], ones[position]
+
+    print(zeros, ones, "pos", position, "remaining lines", len(lines))
+    lines = filter_by_digit(lines, position, "0" if zeros <= ones else "1")
+
+    position += 1
+
+co2 = lines[0]
+
+print(int(oxy, 2) * int(co2, 2))
+
+# 29m