Day 10

2020/day10.py

@@ -0,0 +1,34 @@
+import sys
+
+
+def main():
+    lines = sorted([int(line.rstrip()) for line in sys.stdin])
+    
+    # Part 1
+    diffs = {1: 0, 3: 0}
+    jojo = 0
+    for v in lines:
+        d = v - jojo
+        diffs[d] += 1
+        jojo = v
+    print("Part 1:", diffs[1] * (diffs[3] + 1))
+
+    # Part 2 - yes recursion is fine but have you tried caching your damn values
+    print("Part 2:", rec(0, lines, 0, len(lines), {}))
+
+
+def rec(i, l, n, z, c):
+    if i >= z - 1:
+        return 1
+    if (p := c.get((i, n))) is not None:
+        return p
+    p = 0
+    for ni, nv in enumerate(l[i:i+3]):
+        if n < nv <= n + 3:
+            p += rec(i + ni + 1, l, nv, z, c)
+    c[(i, n)] = p
+    return p
+
+
+if __name__ == "__main__":
+    main()

2020/day9.py

@@ -1,9 +1,9 @@
 import itertools
+import sys
 
 
 def main():
-    with open("day9.txt", "rt") as f:
-        series = [int(line.rstrip()) for line in f.readlines()]
+    series = [int(line.rstrip()) for line in sys.stdin]
     
     # Part 1
     frame_len = 25

2020/new.py

@@ -4,9 +4,11 @@ import os
 from datetime import date
 
 TEMPLATE = """\
+import sys
+
+
 def main():
-    with open("{}", "rt") as f:
-        lines = [line.rstrip() for line in f.readlines()]
+    lines = [line.rstrip() for line in sys.stdin]
 
 
 if __name__ == "__main__":
@@ -15,5 +17,5 @@ if __name__ == "__main__":
 
 day = date.today().day
 with open(f"day{day}.py", "wt") as f:
-    f.write(TEMPLATE.format(f"day{day}.txt"))
+    f.write(TEMPLATE)
 os.system(f"python ../fetch.py {day}")