2016/5

toolkit.py

@@ -1,6 +1,7 @@
 import collections
 import os
 import re
+import subprocess
 import sys
 from pathlib import Path
 
@@ -61,3 +62,9 @@ def get_dat():
     response = requests.get(url, cookies=cookies)
     response.raise_for_status()
     Path(path).write_bytes(response.content)
+
+
+def md5(strings):
+    cmd = ['md5'] + [c for s in strings for c in ['-s', s]]
+    out = subprocess.check_output(cmd).decode()
+    return re.findall(r'"(.+)"\) = (.+)', out)

y2016/p01.py

@@ -0,0 +1,18 @@
+import re
+import sys
+
+
+pos = 0
+ori = 1
+seen = set()
+ans2 = None
+for turn, steps in re.findall(r'(R|L)(\d+)', sys.stdin.read()):
+    ori *= {'R': 1j, 'L': -1j}[turn]
+    for _ in range(int(steps)):
+        pos += ori
+        if ans2 is None and pos in seen:
+            ans2 = abs(pos.real) + abs(pos.imag)
+        seen.add(pos)
+ans1 = abs(pos.real) + abs(pos.imag)
+print(ans1)
+print(ans2)

y2016/p02.py

@@ -0,0 +1,31 @@
+import sys
+
+import toolkit
+
+
+def travel(text, start, image):
+    grid, _, _ = toolkit.read_image(image)
+    pos = {v: k for k, v in grid.items()}[start]
+    for line in text.splitlines():
+        for step in map(moves.get, line):
+            if grid[pos + step].strip():
+                pos += step
+        yield grid[pos]
+
+
+text = sys.stdin.read()
+moves = {'U': -1j, 'L': -1, 'R': 1, 'D': 1j}
+keypad1 = '''
+123
+456
+789
+'''
+keypad2 = '''
+  1
+ 234
+56789
+ ABC
+  D
+'''
+print(''.join(travel(text, '5', keypad1)))
+print(''.join(travel(text, '7', keypad2)))

y2016/p03.py

@@ -0,0 +1,19 @@
+import sys
+
+
+grid = [line.split() for line in sys.stdin.readlines()]
+
+
+ans1 = 0
+for line in grid:
+    a, b, c = sorted(map(int, line))
+    ans1 += a + b > c
+print(ans1)
+
+
+ans2 = 0
+for col in zip(*grid):
+    for line in zip(*[iter(col)] * 3):
+        a, b, c = sorted(map(int, line))
+        ans2 += a + b > c
+print(ans2)

y2016/p04.py

@@ -0,0 +1,25 @@
+import re
+import sys
+from collections import Counter
+
+
+def decode(string, n):
+    def replacer(match):
+        char = match.group(0)
+        return chr((ord(char) + n - ord('a')) % 26 + ord('a'))
+    return re.sub(r'\w', replacer, string)
+
+
+text = sys.stdin.read()
+ans1 = 0
+for line in text.splitlines():
+    name, sid, checksum = re.match(r'^(.+)-(\d+)\[(.+)\]$', line).groups()
+    by_count = ''.join(dict(Counter(sorted(name)).most_common()))
+    calc = by_count.replace('-', '')[:5]
+    if calc == checksum:
+        ans1 += int(sid)
+        decoded = decode(name, int(sid))
+        if 'north' in decoded:
+            ans2 = sid
+print(ans1)
+print(ans2)

y2016/p05.py

@@ -0,0 +1,21 @@
+import itertools
+import sys
+
+import toolkit
+
+
+text = sys.stdin.read().strip()
+password1 = []
+password2 = ['_' for _ in range(8)]
+for i in itertools.count():
+    strings = [f'{text}{1000 * i + k}' for k in range(1000)]
+    for string, digest in toolkit.md5(strings):
+        if digest.startswith('00000'):
+            print(string, digest)
+            password1.append(digest[5])
+            if digest[5] in '01234567' and password2[int(digest[5])] == '_':
+                password2[int(digest[5])] = digest[6]
+    if len(password1) >= 8 and '_' not in password2:
+        break
+print(''.join(password1[:8]))
+print(''.join(password2[:8]))