52 lines
1.0 KiB
Plaintext
52 lines
1.0 KiB
Plaintext
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#!/usr/bin/env python
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import re
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crates = []
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def process_crates(spec):
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for i in range(0, len(spec), 4):
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pos = i // 4
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if len(crates) < pos + 1:
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crates.append([])
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if spec[i] != '[':
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continue
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crates[pos].append(spec[i+1])
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def process_instruction(spec):
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m = re.search('^move (\d+) from (\d+) to (\d+)$', spec)
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count = int(m.group(1))
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src = int(m.group(2)) - 1
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dst = int(m.group(3)) - 1
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items = []
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for i in range(0, count):
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items.append(crates[src].pop())
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items.reverse()
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crates[dst] = crates[dst] + items
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with open('input') as f:
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# Read the diagram + separating line
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for line in f:
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if line[0] == ' ':
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continue
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if line == "\n":
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break
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process_crates(line.rstrip())
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# We filled the lines upside down, so flip them
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for pos in crates:
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pos.reverse()
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for line in f:
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process_instruction(line.rstrip())
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out = ""
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for pos in crates:
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out = out + pos[-1]
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print(out)
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