5

2022/05/README.md

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+# 05
+
+Loved this one! One little gotcha was that (obviously) the crates need to be moved one at a time, meaning reversing the list slice basically.
+Part two is simply to omit reversing the list.
+
+<details>
+  <summary>Solutions</summary>
+  <ol>
+    <li>ZSQVCCJLL</li>
+    <li>QZFJRWHGS</li>
+  </ol>
+</details>

2022/05/python/main.py

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+#!/usr/bin/env python
+
+from dataclasses import dataclass
+from os.path import dirname, join
+
+# Day 05
+
+# Common
+
+
+def read_input(filename):
+    data = join(dirname(__file__), '..', filename)
+    with open(data) as f:
+        return f.read().rstrip()
+
+
+test = read_input('test.txt')
+data = read_input('input.txt')
+
+
+def clean(s: str, words: list[str], strip=True) -> str:
+    for word in words:
+        s = s.replace(word, '')
+    return s.strip() if strip else s
+
+
+@dataclass
+class Operation:
+    amount: int
+    start: int
+    end: int
+
+
+@dataclass
+class Crane:
+    stacks: list[list[str]]
+    operations: list[Operation]
+
+    def operate(self, crate_mover_9001=False):
+        for operation in self.operations:
+            items = self.stacks[operation.start][-operation.amount:]
+            self.stacks[operation.end] += items if crate_mover_9001 else reversed(items)
+            self.stacks[operation.start] = self.stacks[operation.start][:-operation.amount]
+
+    def flag(self):
+        msg = ''
+        for stack in self.stacks:
+            msg += stack[-1]
+        return msg
+
+    @staticmethod
+    def parse(data: str):
+        stacks_raw, operations_raw = data.split('\n\n')
+        operations = [
+            Operation(*map(int, clean(operation, ['move ', 'from ', 'to ']).split(' ')))
+            for operation in operations_raw.split('\n')
+        ]
+        for operation in operations:
+            operation.start -= 1
+            operation.end -= 1
+        stack_lines = stacks_raw.split('\n')
+        stacks_size = len(clean(stack_lines[-1], ['  ']).split(' '))
+        stacks: list[list[str]] = [[] for _ in range(stacks_size)]
+        for line in reversed(stack_lines[:-1]):
+            for i in range(stacks_size):
+                item = line[i*4 + 1]
+                if item != ' ':
+                    stacks[i].append(item)
+        return Crane(stacks, operations)
+
+
+# 1
+print('1.')
+crane = Crane.parse(test)
+crane.operate()
+print(crane.flag())
+
+crane = Crane.parse(data)
+crane.operate()
+print(crane.flag())
+
+# 2
+print('\n2.')
+crane = Crane.parse(test)
+crane.operate(crate_mover_9001=True)
+print(crane.flag())
+
+crane = Crane.parse(data)
+crane.operate(crate_mover_9001=True)
+print(crane.flag())