day 17 part 1 python

day17/sol.py

@@ -0,0 +1,54 @@
+import itertools
+rocks = [
+    0b00011110,
+    0b00001000_00011100_00001000,
+    0b00000100_00000100_00011100,
+    0b00010000_00010000_00010000_00010000,
+    0b00011000_00011000,
+]
+
+jets = itertools.cycle(">>><<><>><<<>><>>><<<>>><<<><<<>><>><<>>")
+jets = itertools.cycle(open("input").read().strip())
+
+rocki = itertools.cycle(rocks)
+
+a = 0b11111111
+wall = 0b10000000_10000000_10000000_10000000_10000000
+stopped = 0
+r = 0
+while stopped < 2022:
+    if r == 0:
+        # start falling
+        r = next(rocki)
+        h = a.bit_length() + 8*3
+        if h % 8 != 0:
+            h += 8 - h%8
+        #for i in reversed(range(0,a.bit_length(),8)):
+        #    print("{:08b}".format((a>>i)&0xff))
+        #print()
+    else:
+        # continue falling?
+        if r & (a>>(h-8)) == 0:
+            h -= 8
+        else:
+            # stop
+            a |= (r<<h)
+            r = 0
+            stopped += 1
+            continue
+
+    j = next(jets)
+    if j == '<':
+        x = (r<<1)
+        if x & wall == 0:
+            if x & (a>>h) == 0:
+                r = x
+    elif j == '>':
+        x = (r<<7)
+        if x & wall == 0:
+            x >>= 8
+            if x & (a>>h) == 0:
+                r = x
+
+import math
+print(math.ceil((a>>8).bit_length()/8))