Add day 5 solution

05/crates.py

@@ -0,0 +1,74 @@
+
+import fileinput
+from typing import Iterable,List
+
+class Puzzle:
+    stacks: List[List[str]]
+    instructions: List[str]
+
+    def __init__(self):
+        self.stacks = []
+        self.instructions = []
+
+def parse(lines: Iterable[str]) -> Puzzle:
+    count = None
+    stage = 0
+    puzzle = Puzzle()
+    for line in map(lambda x: x.replace('\n',''), lines):
+        if count is None: # Figure out how many stacks
+            count = len(line)//4 + 1
+            for _ in range(count):
+                puzzle.stacks.append([])
+            #puzzle.stacks = [[]]*count
+        if stage == 0:
+            if '[' not in line:
+                stage = 1
+                continue
+            chars = [line[i*4+1:i*4+2] for i in range(count)]
+            for idx in range(count):
+                if chars[idx] != ' ':
+                    puzzle.stacks[idx].append(chars[idx])
+        elif stage == 1:
+            stage = 2
+        elif stage == 2:
+            puzzle.instructions.append(line)
+    for idx in range(count):
+        puzzle.stacks[idx] = puzzle.stacks[idx][::-1]
+    return puzzle
+
+def solve(p: Puzzle) -> str:
+    for ins in p.instructions:
+        _, cnt, _, fr, _, to = ins.split(' ')
+        cnt = int(cnt)
+        fr = int(fr)
+        to = int(to)
+        for _ in range(cnt):
+            p.stacks[to-1].append(p.stacks[fr-1].pop())
+    out = ''
+    for st in p.stacks:
+        out += st[-1]
+    return out
+
+def solveb(p: Puzzle) -> str:
+    for ins in p.instructions:
+        _, cnt, _, fr, _, to = ins.split(' ')
+        cnt = int(cnt)
+        fr = int(fr)
+        to = int(to)
+        load = []
+        for _ in range(cnt):
+            load.append(p.stacks[fr-1].pop())
+        load = load[::-1]
+        p.stacks[to-1] += load
+    out = ''
+    for st in p.stacks:
+        out += st[-1]
+    return out
+
+
+if __name__ == "__main__":
+    puzzle = parse(fileinput.input())
+    print(solve(puzzle))
+    puzzle = parse(fileinput.input())
+    print(solveb(puzzle))
+

05/example

@@ -0,0 +1,9 @@
+    [D]    
+[N] [C]    
+[Z] [M] [P]
+ 1   2   3 
+
+move 1 from 2 to 1
+move 3 from 1 to 3
+move 2 from 2 to 1
+move 1 from 1 to 2