From e5acaa81e6deaaf4fa1fa06748e7eb4a0949c30a Mon Sep 17 00:00:00 2001
From: cupcakearmy <hi@nicco.io>
Date: Fri, 3 Dec 2021 08:58:31 +0100
Subject: [PATCH] day 3

---
 2021/03/README.md      | 11 ++++++
 2021/03/python/main.py | 90 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 101 insertions(+)
 create mode 100644 2021/03/README.md
 create mode 100644 2021/03/python/main.py

diff --git a/2021/03/README.md b/2021/03/README.md
new file mode 100644
index 0000000..a7210a4
--- /dev/null
+++ b/2021/03/README.md
@@ -0,0 +1,11 @@
+# 03
+
+Description
+
+<details>
+  <summary>Solutions</summary>
+  <ol>
+    <li>Gamma: 3903, Epsilon: 192, Power Consumption: 749376</li>
+    <li>Oxygen: 3871, CO2: 613, Life Support: 2372923</li>
+  </ol>
+</details>
diff --git a/2021/03/python/main.py b/2021/03/python/main.py
new file mode 100644
index 0000000..781172a
--- /dev/null
+++ b/2021/03/python/main.py
@@ -0,0 +1,90 @@
+#!/usr/bin/env python
+
+from os import O_EXCL
+from os.path import join, dirname
+from typing import Tuple
+
+# Day 03
+
+# Common
+
+
+def read_input(filename):
+    data = join(dirname(__file__), '..', filename)
+    with open(data) as f:
+        return f.read().strip()
+
+
+test = read_input('test.txt')
+data = read_input('input.txt')
+
+# 1
+
+
+def count_bits(input: str) -> Tuple[int, int]:
+    gamma = 0
+    epsilon = 0
+    lines = input.split('\n')
+    size = len(lines[0])
+    for x in range(size):
+        zeros = 0
+        ones = 0
+        for line in lines:
+            if line[x] == '0':
+                zeros += 1
+            else:
+                ones += 1
+        incr = 2**(size - x - 1)
+        if zeros < ones:
+            gamma += incr
+        else:
+            epsilon += incr
+    return gamma, epsilon
+
+
+print('1.')
+gamma, epsilon = count_bits(test)
+print(
+    f"Test: Gamma: {gamma}, Epsilon: {epsilon}, Power Consumption: {gamma * epsilon}")
+gamma, epsilon = count_bits(data)
+print(
+    f"Data: Gamma: {gamma}, Epsilon: {epsilon}, Power Consumption: {gamma * epsilon}")
+# 2
+
+
+def extract(input: str, bigger=True) -> int:
+    lines = input.split('\n')
+    size = len(lines[0])
+    for x in range(size):
+        zeros = 0
+        ones = 0
+        for line in lines:
+            if line[x] == '0':
+                zeros += 1
+            else:
+                ones += 1
+        if zeros == ones:
+            filter = '1' if bigger else '0'
+        elif bigger:
+            filter = '0' if zeros > ones else '1'
+        else:
+            filter = '0' if zeros < ones else '1'
+        lines = [
+            line for line in lines
+            if line[x] == filter
+        ]
+        if len(lines) == 1:
+            return int(lines[0], 2)
+    raise Exception('No solution found')
+
+
+print('\n2.')
+oxygen = extract(test, True)
+co2 = extract(test, False)
+life_support = oxygen * co2
+print(f"Test: Oxygen: {oxygen}, CO2: {co2}, Life Support: {life_support}")
+
+oxygen = extract(data, True)
+co2 = extract(data, False)
+life_support = oxygen * co2
+print(f"Data: Oxygen: {oxygen}, CO2: {co2}, Life Support: {life_support}")