Advent of Code - preparing input data
When solving Advent of Code puzzles, sometimes you will come across an input data, that consist of two parts: configuration and instructions:
[S] [C] [Z]
[F] [J] [P] [T] [N]
[G] [H] [G] [Q] [G] [D]
[V] [V] [D] [G] [F] [D] [V]
[R] [B] [F] [N] [N] [Q] [L] [S]
[J] [M] [M] [P] [H] [V] [B] [B] [D]
[L] [P] [H] [D] [L] [F] [D] [J] [L]
[D] [T] [V] [M] [J] [N] [F] [M] [G]
1 2 3 4 5 6 7 8 9
move 3 from 4 to 6
move 1 from 5 to 8
move 3 from 7 to 3
move 4 from 5 to 7
move 1 from 7 to 8
move 3 from 9 to 4
While it's perfectly fine to write some kind of parser for it, very often I manually make the data easier to work with, which can be super fast thanks to text editor features, like multiline-cursor, or select all occurrences.
For example, with this particular puzzle, I thought that it might be a good idea to store the first part of the input as an object, so I manually typed the stack for each column, and then used multiline-cursor to append split part of the code. It took me only couple of seconds, definitely much faster than writing the whole parser for it.
let MAP = {
1: 'DLJRVGF'.split(''),
2: 'TPMBVHJS'.split(''),
3: 'VHMFDGPC'.split(''),
4: 'MDPNGQ'.split(''),
5: 'JLHNF'.split(''),
6: 'NFVQDGTZ'.split(''),
7: 'FDBL'.split(''),
8: 'MJBSVDN'.split(''),
9: 'GLD'.split(''),
}
Second part, wouldn't require that much parsing, but still, instead of doing that, I removed the text by selecting all occurrences, and left only important bits of information:
3 4 6
1 5 8
3 7 3
4 5 7
1 7 8
3 9 4
2 8 2
With that, I could iterate over list of steps pretty easily:
let instructions = input
.split('\n')
.map(i => i.split(' ')
.map(Number))
for (let [quantity, from, to] of instructions) {
...
}