advent_of_code_2021

commit 2a907e61f669b35fe9260f01175bc8e4b8ed8c46
parent 1382a599ad70cc4124cc5c7946c6ff39d5bd0556
Author: Eamon Caddigan <eamon.caddigan@gmail.com>
Date:   Wed,  8 Dec 2021 11:12:22 -0500

Just comments, prepared to solve the puzzle soon

Diffstat:
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day08_part1.py
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diff --git a/day08_part1.py b/day08_part1.py
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+#!/usr/bin/env python
+"""Advent of Code 2021, day 8 (part 1): decode the scrambled seven-segment
+displays"""
+
+# This is a fun puzzle. I sat down with pen and paper and proved to myself that
+# you can deduce the mapping from scrambled segments to the full set of digits
+# using just the information provided. It looks like this:
+# * If 2 segments are lit, that's '1'
+# * If 3 segments are lit, that's '7'
+# * If 4 segments are lit, that's '4'
+# * If 7 segments are lit, that's '8'
+# (So far, this was given in the puzzle prompt, nothing new yet)
+# * If 5 segments are lit, it's '2', '3', or '5'
+# * If 6 segments are lit, it's '0', '6', or '9'
+# (Okay, that's not useful... yet)
+# * If 5 segments are lit and they include all the segments in '7', that's '3'
+# * If 6 segments are lit and they don't include all the segments in '7',
+#   that's '6'
+# * If 6 segments are lit and they include the union of the segments comprising
+#   '3' and '4', that's '9'
+# * If 6 segments are lit and it's not a '6' or '9', that's '0'
+# * If 5 segments are lit and it is missing only one of the segments from '6',
+#   that's '2'
+# * If 5 segments are lit and it's not a '2' or a '3', that's '5'
+# So right now in part 1, it's possible to find the four digits displayed for
+# each line of puzzle input! But...
+# I'm not going to implement it yet, because "good programmers are lazy", and
+# maybe part 2 will throw me for a loop? Regardless, figuring this out has
+# influenced my decision about how to represent the data; i.e., we're doing a
+# lot of set operations, so I'm going to use sets for everything, and since
+# it's easy to imagine wanting to use these sets of lit segments as dictionary
+# keys, we'll use immutable `frozenset`s specifically (which can be `dict`
+# keys).
+
+EXAMPLE_INPUT = \
+"""be cfbegad cbdgef fgaecd cgeb fdcge agebfd fecdb fabcd edb | fdgacbe cefdb cefbgd gcbe
+edbfga begcd cbg gc gcadebf fbgde acbgfd abcde gfcbed gfec | fcgedb cgb dgebacf gc
+fgaebd cg bdaec gdafb agbcfd gdcbef bgcad gfac gcb cdgabef | cg cg fdcagb cbg
+fbegcd cbd adcefb dageb afcb bc aefdc ecdab fgdeca fcdbega | efabcd cedba gadfec cb
+aecbfdg fbg gf bafeg dbefa fcge gcbea fcaegb dgceab fcbdga | gecf egdcabf bgf bfgea
+fgeab ca afcebg bdacfeg cfaedg gcfdb baec bfadeg bafgc acf | gebdcfa ecba ca fadegcb
+dbcfg fgd bdegcaf fgec aegbdf ecdfab fbedc dacgb gdcebf gf | cefg dcbef fcge gbcadfe
+bdfegc cbegaf gecbf dfcage bdacg ed bedf ced adcbefg gebcd | ed bcgafe cdgba cbgef
+egadfb cdbfeg cegd fecab cgb gbdefca cg fgcdab egfdb bfceg | gbdfcae bgc cg cgb
+gcafb gcf dcaebfg ecagb gf abcdeg gaef cafbge fdbac fegbdc | fgae cfgab fg bagce
+"""