Optimize the hell out of day02

This commit is contained in:
2025-12-03 19:55:51 -05:00
parent 3d001c690f
commit 8e163be240
4 changed files with 167 additions and 95 deletions

102
Cargo.lock generated
View File

@@ -25,6 +25,7 @@ dependencies = [
"color-eyre",
"criterion",
"itertools 0.14.0",
"rayon",
"test-log",
"tracing",
"tracing-error",
@@ -40,6 +41,15 @@ dependencies = [
"memchr",
]
[[package]]
name = "alloca"
version = "0.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "e5a7d05ea6aea7e9e64d25b9156ba2fee3fdd659e34e41063cd2fc7cd020d7f4"
dependencies = [
"cc",
]
[[package]]
name = "anes"
version = "0.1.6"
@@ -129,6 +139,16 @@ version = "0.3.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "37b2a672a2cb129a2e41c10b1224bb368f9f37a2b16b612598138befd7b37eb5"
[[package]]
name = "cc"
version = "1.2.48"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "c481bdbf0ed3b892f6f806287d72acd515b352a4ec27a208489b8c1bc839633a"
dependencies = [
"find-msvc-tools",
"shlex",
]
[[package]]
name = "cfg-if"
version = "1.0.4"
@@ -237,25 +257,24 @@ checksum = "b05b61dc5112cbb17e4b6cd61790d9845d13888356391624cbe7e41efeac1e75"
[[package]]
name = "criterion"
version = "0.5.1"
version = "0.8.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "f2b12d017a929603d80db1831cd3a24082f8137ce19c69e6447f54f5fc8d692f"
checksum = "a0dfe5e9e71bdcf4e4954f7d14da74d1cdb92a3a07686452d1509652684b1aab"
dependencies = [
"alloca",
"anes",
"cast",
"ciborium",
"clap",
"criterion-plot",
"is-terminal",
"itertools 0.10.5",
"itertools 0.13.0",
"num-traits",
"once_cell",
"oorandom",
"page_size",
"plotters",
"rayon",
"regex",
"serde",
"serde_derive",
"serde_json",
"tinytemplate",
"walkdir",
@@ -263,12 +282,12 @@ dependencies = [
[[package]]
name = "criterion-plot"
version = "0.5.0"
version = "0.8.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "6b50826342786a51a89e2da3a28f1c32b06e387201bc2d19791f622c673706b1"
checksum = "5de36c2bee19fba779808f92bf5d9b0fa5a40095c277aba10c458a12b35d21d6"
dependencies = [
"cast",
"itertools 0.10.5",
"itertools 0.13.0",
]
[[package]]
@@ -318,6 +337,12 @@ dependencies = [
"once_cell",
]
[[package]]
name = "find-msvc-tools"
version = "0.1.5"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "3a3076410a55c90011c298b04d0cfa770b00fa04e1e3c97d3f6c9de105a03844"
[[package]]
name = "gimli"
version = "0.32.3"
@@ -341,29 +366,12 @@ version = "0.5.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
[[package]]
name = "hermit-abi"
version = "0.5.2"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "fc0fef456e4baa96da950455cd02c081ca953b141298e41db3fc7e36b1da849c"
[[package]]
name = "indenter"
version = "0.3.4"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "964de6e86d545b246d84badc0fef527924ace5134f30641c203ef52ba83f58d5"
[[package]]
name = "is-terminal"
version = "0.4.17"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "3640c1c38b8e4e43584d8df18be5fc6b0aa314ce6ebf51b53313d4306cca8e46"
dependencies = [
"hermit-abi",
"libc",
"windows-sys 0.61.2",
]
[[package]]
name = "is_terminal_polyfill"
version = "1.70.2"
@@ -372,9 +380,9 @@ checksum = "a6cb138bb79a146c1bd460005623e142ef0181e3d0219cb493e02f7d08a35695"
[[package]]
name = "itertools"
version = "0.10.5"
version = "0.13.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "b0fd2260e829bddf4cb6ea802289de2f86d6a7a690192fbe91b3f46e0f2c8473"
checksum = "413ee7dfc52ee1a4949ceeb7dbc8a33f2d6c088194d9f922fb8318faf1f01186"
dependencies = [
"either",
]
@@ -497,6 +505,16 @@ version = "4.2.3"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "9c6901729fa79e91a0913333229e9ca5dc725089d1c363b2f4b4760709dc4a52"
[[package]]
name = "page_size"
version = "0.6.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "30d5b2194ed13191c1999ae0704b7839fb18384fa22e49b57eeaa97d79ce40da"
dependencies = [
"libc",
"winapi",
]
[[package]]
name = "pin-project-lite"
version = "0.2.16"
@@ -677,6 +695,12 @@ dependencies = [
"lazy_static",
]
[[package]]
name = "shlex"
version = "1.3.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
[[package]]
name = "smallvec"
version = "1.15.1"
@@ -894,6 +918,22 @@ dependencies = [
"wasm-bindgen",
]
[[package]]
name = "winapi"
version = "0.3.9"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
dependencies = [
"winapi-i686-pc-windows-gnu",
"winapi-x86_64-pc-windows-gnu",
]
[[package]]
name = "winapi-i686-pc-windows-gnu"
version = "0.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
[[package]]
name = "winapi-util"
version = "0.1.11"
@@ -903,6 +943,12 @@ dependencies = [
"windows-sys 0.61.2",
]
[[package]]
name = "winapi-x86_64-pc-windows-gnu"
version = "0.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
[[package]]
name = "windows-link"
version = "0.2.1"

View File

@@ -7,12 +7,13 @@ edition = "2024"
clap = { version = "4.5", features = ["derive"] }
color-eyre = "0.6"
itertools = "0.14"
rayon = "1.11"
tracing = "0.1"
tracing-error = "0.2"
tracing-subscriber = { version = "0.3", features = ["env-filter"] }
[dev-dependencies]
criterion = "0.5.1"
criterion = "0.8.0"
test-log = { version = "0.2", default-features = false, features = ["trace"] }
# Improve perf on debug builds: https://docs.rs/color-eyre/latest/color_eyre/#improving-perf-on-debug-builds

View File

@@ -33,4 +33,4 @@ Timings are given as: [lower-bound **best-estimate** upper-bound]
| Day | Part 1 | Part 2 |
|-----|--------|--------|
| 01 | [101.34 µs **101.95 µs** 102.61 µs] | [105.90 µs **106.40 µs** 106.95 µs] |
| 02 | [165.59 ms **166.60 ms** 167.65 ms] | [184.17 ms **185.25 ms** 186.42 ms] |
| 02 | [2.0990 ms **2.1113 ms** 2.1236 ms] | [2.0954 ms **2.1055 ms** 2.1157 ms] |

View File

@@ -2,9 +2,9 @@ use std::{fmt::Display, str::FromStr};
use color_eyre::{
Result,
eyre::{Error, OptionExt, eyre},
eyre::{Error, eyre},
};
use itertools::Itertools;
use rayon::prelude::*;
use tracing::{debug, debug_span, instrument};
pub const INPUT: &str = include_str!("input/input.txt");
@@ -50,69 +50,86 @@ impl Iterator for ProductRange {
}
}
fn is_valid_product_id(id: i64) -> Result<bool> {
let digits: Vec<u32> = id
.to_string()
.chars()
.map(|c| {
c.to_digit(10)
.ok_or_eyre("Invalid product id: contains a non-decimal digit")
})
.collect::<Result<Vec<u32>>>()?;
if digits.len() % 2 != 0 {
return Ok(true);
}
Ok(digits[..digits.len() / 2] != digits[digits.len() / 2..])
}
fn is_valid_product_id2(id: i64) -> Result<bool> {
let digits: Vec<u32> = id
.to_string()
.chars()
.map(|c| {
c.to_digit(10)
.ok_or_eyre("Invalid product id: contains a non-decimal digit")
})
.collect::<Result<Vec<u32>>>()?;
let mut chunk_size = digits.len() / 2;
loop {
if chunk_size == 0 {
break;
}
if digits
.chunks(chunk_size)
.tuple_windows()
.all(|(a, b)| a == b)
{
return Ok(false);
}
chunk_size -= 1;
}
Ok(true)
}
impl ProductRange {
fn invalid_ids(self) -> Result<Vec<i64>> {
let mut invalid_ids = vec![];
let start = *self.0.start();
let end = *self.0.end();
for id in self {
if !is_valid_product_id(id)? {
let mut invalid_ids = Vec::new();
// Determine digit ranges we need to check
let start_digits = if start == 0 { 1 } else { start.ilog10() + 1 };
let end_digits = if end == 0 { 1 } else { end.ilog10() + 1 };
for num_digits in start_digits..=end_digits {
// Skip odd digit counts - they're all valid
if num_digits % 2 != 0 {
continue;
}
let half_digits = num_digits / 2;
let half_min = 10_i64.pow(half_digits - 1);
let half_max = 10_i64.pow(half_digits) - 1;
let multiplier = 10_i64.pow(half_digits) + 1; // Pre-calculate: half * multiplier = AABB pattern
// Generate all patterns where first half == second half
for half in half_min..=half_max {
let id = half * multiplier;
if id >= start && id <= end {
invalid_ids.push(id);
}
}
}
debug!("Invalid IDs: {:?}", &invalid_ids);
Ok(invalid_ids)
}
fn invalid_ids2(self) -> Result<Vec<i64>> {
let mut invalid_ids = vec![];
let start = *self.0.start();
let end = *self.0.end();
for id in self {
if !is_valid_product_id2(id)? {
invalid_ids.push(id);
let mut invalid_ids = std::collections::HashSet::new();
// Determine digit ranges we need to check
let start_digits = if start == 0 { 1 } else { start.ilog10() + 1 };
let end_digits = if end == 0 { 1 } else { end.ilog10() + 1 };
for num_digits in start_digits..=end_digits {
// Try all possible chunk sizes that divide evenly
for chunk_size in 1..=num_digits / 2 {
if num_digits % chunk_size != 0 {
continue;
}
let num_chunks = num_digits / chunk_size;
if num_chunks < 2 {
continue;
}
// Generate all possible chunk patterns
let chunk_min = 10_i64.pow(chunk_size - 1);
let chunk_max = 10_i64.pow(chunk_size) - 1;
let chunk_power = 10_i64.pow(chunk_size);
// Calculate multiplier for repeating pattern
// For ABCABC: chunk * (10^6 + 10^3 + 1) = chunk * 1001001
let mut multiplier = 0_i64;
for i in 0..num_chunks {
multiplier += chunk_power.pow(i);
}
for chunk in chunk_min..=chunk_max {
let id = chunk * multiplier;
if id >= start && id <= end {
invalid_ids.insert(id);
}
}
}
}
let invalid_ids: Vec<i64> = invalid_ids.into_iter().collect();
debug!("Invalid IDs: {:?}", &invalid_ids);
Ok(invalid_ids)
@@ -121,24 +138,32 @@ impl ProductRange {
#[instrument(skip(input))]
pub fn part1(input: &str) -> Result<i64> {
let mut total_invalid = 0;
for range in input.trim().split(',') {
input
.trim()
.split(',')
.collect::<Vec<_>>()
.into_par_iter()
.map(|range| {
let _span = debug_span!("range", range = %range).entered();
let range: ProductRange = range.parse()?;
total_invalid += range.invalid_ids()?.iter().sum::<i64>();
}
Ok(total_invalid)
Ok(range.invalid_ids()?.iter().sum::<i64>())
})
.sum()
}
#[instrument(skip(input))]
pub fn part2(input: &str) -> Result<i64> {
let mut total_invalid = 0;
for range in input.trim().split(',') {
input
.trim()
.split(',')
.collect::<Vec<_>>()
.into_par_iter()
.map(|range| {
let _span = debug_span!("range", range = %range).entered();
let range: ProductRange = range.parse()?;
total_invalid += range.invalid_ids2()?.iter().sum::<i64>();
}
Ok(total_invalid)
Ok(range.invalid_ids2()?.iter().sum::<i64>())
})
.sum()
}
#[cfg(test)]