ktims/aoc2023
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

day5: problem 2 solution. parallelized!

Browse Source
This commit is contained in:
Keenan Tims 2023-12-06 17:24:24 -08:00
parent 0665e109af
commit 077f4ff8ee
No known key found for this signature in database
GPG Key ID: B8FDD4AD6B193F06
3 changed files with 164 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

99
5/Cargo.lock generated
View File

@ -2,6 +2,105 @@
# It is not intended for manual editing.
version = 3
[[package]]
name = "autocfg"
version = "1.1.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
[[package]]
name = "cfg-if"
version = "1.0.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
[[package]]
name = "crossbeam-deque"
version = "0.8.3"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "ce6fd6f855243022dcecf8702fef0c297d4338e226845fe067f6341ad9fa0cef"
dependencies = [
"cfg-if",
"crossbeam-epoch",
"crossbeam-utils",
]
[[package]]
name = "crossbeam-epoch"
version = "0.9.15"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "ae211234986c545741a7dc064309f67ee1e5ad243d0e48335adc0484d960bcc7"
dependencies = [
"autocfg",
"cfg-if",
"crossbeam-utils",
"memoffset",
"scopeguard",
]
[[package]]
name = "crossbeam-utils"
version = "0.8.16"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "5a22b2d63d4d1dc0b7f1b6b2747dd0088008a9be28b6ddf0b1e7d335e3037294"
dependencies = [
"cfg-if",
]
[[package]]
name = "day5"
version = "0.1.0"
dependencies = [
"itertools",
"rayon",
]
[[package]]
name = "either"
version = "1.9.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "a26ae43d7bcc3b814de94796a5e736d4029efb0ee900c12e2d54c993ad1a1e07"
[[package]]
name = "itertools"
version = "0.12.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "25db6b064527c5d482d0423354fcd07a89a2dfe07b67892e62411946db7f07b0"
dependencies = [
"either",
]
[[package]]
name = "memoffset"
version = "0.9.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "5a634b1c61a95585bd15607c6ab0c4e5b226e695ff2800ba0cdccddf208c406c"
dependencies = [
"autocfg",
]
[[package]]
name = "rayon"
version = "1.8.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "9c27db03db7734835b3f53954b534c91069375ce6ccaa2e065441e07d9b6cdb1"
dependencies = [
"either",
"rayon-core",
]
[[package]]
name = "rayon-core"
version = "1.12.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "5ce3fb6ad83f861aac485e76e1985cd109d9a3713802152be56c3b1f0e0658ed"
dependencies = [
"crossbeam-deque",
"crossbeam-utils",
]
[[package]]
name = "scopeguard"
version = "1.2.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"

2
5/Cargo.toml
View File

@ -6,3 +6,5 @@ edition = "2021"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
itertools = "0.12.0"
rayon = "1.8.0"

66
5/src/main.rs
View File

@ -2,6 +2,9 @@ use std::fs::File;
use std::io::{BufRead, BufReader, Lines};
use std::ops::Range;
use itertools::Itertools;
use rayon::prelude::*;
// --- Day 5: If You Give A Seed A Fertilizer ---
// You take the boat and find the gardener right where you were told he would be:
@ -278,7 +281,12 @@ impl Almanac {
// What is the lowest location number that corresponds to any of the initial seed numbers?
fn problem1_lowest_location(almanac: &Almanac) -> u64 {
almanac.seeds.iter().map(|seed| almanac.lookup(*seed)).min().unwrap()
almanac
.seeds
.iter()
.map(|seed| almanac.lookup(*seed))
.min()
.unwrap()
}
fn problem1<T: BufRead>(input: Lines<T>) -> u64 {
@ -287,15 +295,60 @@ fn problem1<T: BufRead>(input: Lines<T>) -> u64 {
}
// PROBLEM 2 solution
// Everyone will starve if you only plant such a small number of seeds. Re-reading the
// almanac, it looks like the seeds: line actually describes ranges of seed numbers.
// The values on the initial seeds: line come in pairs. Within each pair, the first
// value is the start of the range and the second value is the length of the range. So,
// in the first line of the example above:
// seeds: 79 14 55 13
// This line describes two ranges of seed numbers to be planted in the garden. The first
// range starts with seed number 79 and contains 14 values: 79, 80, ..., 91, 92. The
// second range starts with seed number 55 and contains 13 values: 55, 56, ..., 66, 67.
// Now, rather than considering four seed numbers, you need to consider a total of 27
// seed numbers.
// In the above example, the lowest location number can be obtained from seed number 82,
// which corresponds to soil 84, fertilizer 84, water 84, light 77, temperature 45,
// humidity 46, and location 46. So, the lowest location number is 46.
// Consider all of the initial seed numbers listed in the ranges on the first line of
// the almanac. What is the lowest location number that corresponds to any of the
// initial seed numbers?
fn problem2_lowest_location(almanac: &Almanac) -> u64 {
let seed_ranges = almanac
.seeds
.iter()
.tuples()
.map(|(range_start, length)| *range_start..*range_start + *length);
seed_ranges
.map(|range| {
range
.into_par_iter()
.map(|x| almanac.lookup(x))
.min()
.unwrap()
})
.min()
.unwrap()
}
fn problem2<T: BufRead>(input: Lines<T>) -> u64 {
0
let almanac = Almanac::from(input);
problem2_lowest_location(&almanac)
}
#[cfg(test)]
mod tests {
use std::io::{BufRead, Cursor};
use crate::{Almanac, AlmanacMapping, problem1_lowest_location};
use crate::*;
const EXAMPLE_ALMANAC: &str = &"seeds: 79 14 55 13
@ -359,4 +412,11 @@ humidity-to-location map:
let a = Almanac::from(c.lines());
assert_eq!(problem1_lowest_location(&a), 35);
}
#[test]
fn test_problem2_example() {
let c = Cursor::new(EXAMPLE_ALMANAC);
let a = Almanac::from(c.lines());
assert_eq!(problem2_lowest_location(&a), 46);
}
}