Day 16

advent_tools.py

@@ -395,5 +395,5 @@ def md5_increment(salt):
 
 if __name__ == '__main__':
     # start_coding_today()
-    today = 15
+    today = 16
     start_coding(today)

day16/day16.py

@@ -0,0 +1,44 @@
+import contextlib
+import collections
+import copy
+import functools
+import itertools
+import numpy as np
+import pandas as pd
+import re
+
+import advent_tools
+
+
+def calc_checksum(start_data, needed_length):
+    data = make_right_length(start_data, needed_length)
+    while len(data) and len(data) % 2 == 0:
+        print(len(data))
+        new_data = ''
+        for first, second in zip(data[0::2], data[1::2]):
+            if first == second:
+                new_data = new_data + '1'
+            else:
+                new_data = new_data + '0'
+        data = new_data
+    return data
+
+def make_right_length(start_data, needed_length):
+    data = start_data
+    while len(data) < needed_length:
+        rev = ''.join(['1' if a == '0' else '0' for a in reversed(data)])
+        data = data + '0' + rev
+    return data[:needed_length]
+
+
+def run_part_1():
+    print(calc_checksum('11110010111001001', 272))
+
+
+def run_part_2():
+    print(calc_checksum('11110010111001001', 35651584))
+
+
+if __name__ == '__main__':
+    run_part_1()
+    run_part_2()

day16/input.txt

@@ -0,0 +1 @@
+11110010111001001