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‎2024/README.md

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# Advent of Code in Rust 🦀
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![AoC2024](https://img.shields.io/badge/Advent_of_Code-2024-8A2BE2)
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![Stars: 12](https://img.shields.io/badge/Stars-12⭐-blue)
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![Rust: 6](https://img.shields.io/badge/Rust-6-cyan?logo=Rust)
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![Python: 4](https://img.shields.io/badge/Python-4-cyan?logo=Python)
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![Stars: 14](https://img.shields.io/badge/Stars-14⭐-blue)
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![Rust: 7](https://img.shields.io/badge/Rust-7-cyan?logo=Rust)
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![Python: 5](https://img.shields.io/badge/Python-5-cyan?logo=Python)
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## 2024 ([Calendar](https://adventofcode.com/2024)) ([Solutions](../2024/)) : 12⭐
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## 2024 ([Calendar](https://adventofcode.com/2024)) ([Solutions](../2024/)) : 14⭐
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Puzzle | Stars | Languages
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---------------------------------------------------------------- | ----- | -----------
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[Day 4: Ceres Search](https://adventofcode.com/2024/day/4) | ⭐⭐ | [![Rust](../scripts/assets/rust.png)](../2024/day4/day4.rs) [![Python](../scripts/assets/python.png)](../2024/day4/day4.py)
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[Day 5: Print Queue](https://adventofcode.com/2024/day/5) | ⭐⭐ | [![Rust](../scripts/assets/rust.png)](../2024/day5/day5.rs)
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[Day 6: Guard Gallivant](https://adventofcode.com/2024/day/6) | ⭐⭐ | [![Rust](../scripts/assets/rust.png)](../2024/day6/day6.rs)
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[Day 7: Bridge Repair](https://adventofcode.com/2024/day/7) | ⭐⭐ | [![Rust](../scripts/assets/rust.png)](../2024/day7/day7.rs) [![Python](../scripts/assets/python.png)](../2024/day7/day7.py)

‎2024/day7/Cargo.toml

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[package]
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name = "day7"
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version = "0.1.0"
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edition = "2021"
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[dependencies]
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aoc = { path = "../../aoc" }
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[[bin]]
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name = "day7"
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path = "day7.rs"

‎2024/day7/day7.rs

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//! [Day 7: Bridge Repair](https://adventofcode.com/2024/day/7)
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// use std::collections::{HashMap,HashSet};
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struct Equation {
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test_value: u64,
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values: Vec<u64>,
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}
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struct Puzzle {
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equations: Vec<Equation>,
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}
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impl Puzzle {
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fn new() -> Puzzle {
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Puzzle {
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equations: Vec::new(),
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}
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}
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/// Get the puzzle input.
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fn configure(&mut self, path: &str) {
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let data = std::fs::read_to_string(path).unwrap();
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for line in data.lines() {
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let (test_value, values) = line.split_once(':').unwrap();
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let equation = Equation {
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test_value: test_value.parse().unwrap(),
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values: values
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.split_ascii_whitespace()
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.map(|x| x.parse().unwrap())
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.collect(),
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};
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self.equations.push(equation);
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}
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}
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/// Check if there is a combination of operators + and * that solves the equation
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fn check_two_operators(equation: &Equation) -> bool {
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// the number of operations
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let n = (equation.values.len() - 1).try_into().unwrap();
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// iterate over all combinations
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for mut i in 0..2_u32.pow(n) {
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let mut result = equation.values[0];
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for value in &equation.values[1..] {
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if i % 2 == 0 {
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result += value;
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} else {
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result *= value;
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}
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i /= 2;
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if result > equation.test_value {
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// unnecessary to continue: result will never equal test value
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break;
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}
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}
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if result == equation.test_value {
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return true;
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}
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}
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false
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}
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/// Check if there is a combination of operators + * || that solves the equation
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fn check_three_operators(equation: &Equation) -> bool {
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// pre-compute the power of 10 for operator ||
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let mut pow10 = Vec::new();
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for value in &equation.values[1..] {
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let mut p = 1;
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let mut value = *value;
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while value != 0 {
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p *= 10;
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value /= 10;
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}
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pow10.push(p);
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}
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// the number of operations
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let n = (equation.values.len() - 1).try_into().unwrap();
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// iterate over all combinations
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for mut i in 0..3_u32.pow(n) {
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let mut result = equation.values[0];
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for (k, value) in equation.values[1..].iter().enumerate() {
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result = match i % 3 {
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0 => result + value,
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1 => result * value,
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_ => result * pow10[k] + value,
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};
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i /= 3;
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if result > equation.test_value {
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break;
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}
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}
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if result == equation.test_value {
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return true;
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}
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}
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false
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}
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/// Solve part one.
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fn part1(&self) -> u64 {
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self.equations
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.iter()
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.filter(|e| Self::check_two_operators(e))
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.map(|x| x.test_value)
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.sum()
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}
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/// Solve part two.
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fn part2(&self) -> u64 {
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self.equations
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.iter()
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.filter(|e| Self::check_three_operators(e))
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.map(|x| x.test_value)
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.sum()
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}
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}
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fn main() {
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let args = aoc::parse_args();
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let mut puzzle = Puzzle::new();
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puzzle.configure(args.path.as_str());
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println!("{}", puzzle.part1());
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println!("{}", puzzle.part2());
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}
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/// Test from puzzle input
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#[cfg(test)]
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mod test {
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use super::*;
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#[test]
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fn test01() {
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let mut puzzle = Puzzle::new();
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puzzle.configure("test.txt");
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assert_eq!(puzzle.part1(), 3749);
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}
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#[test]
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fn test02() {
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let mut puzzle = Puzzle::new();
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puzzle.configure("test.txt");
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assert_eq!(puzzle.part2(), 11387);
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}
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}

‎2024/day7/test.txt

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190: 10 19
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3267: 81 40 27
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83: 17 5
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156: 15 6
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7290: 6 8 6 15
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161011: 16 10 13
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192: 17 8 14
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21037: 9 7 18 13
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292: 11 6 16 20

‎README.md

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# Advent of Code in Rust 🦀
22

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![Stars: 462](https://img.shields.io/badge/Stars-462⭐-blue)
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![Rust: 177](https://img.shields.io/badge/Rust-177-cyan?logo=Rust)
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![Python: 117](https://img.shields.io/badge/Python-117-cyan?logo=Python)
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![Stars: 464](https://img.shields.io/badge/Stars-464⭐-blue)
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![Rust: 178](https://img.shields.io/badge/Rust-178-cyan?logo=Rust)
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![Python: 118](https://img.shields.io/badge/Python-118-cyan?logo=Python)
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Solutions of [Advent of Code](https://adventofcode.com/) in [Rust](https://www.rust-lang.org), and sometimes in [Python](https://www.python.org/).
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Made for fun 😎 and to practice Rust. Many thanks to [Eric Wastl](https://twitter.com/ericwastl).
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## 2024 (current event) ([Calendar](https://adventofcode.com/2024)) ([Solutions](2024/)) : 12⭐
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## 2024 (current event) ([Calendar](https://adventofcode.com/2024)) ([Solutions](2024/)) : 14⭐
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Puzzle | Stars | Languages
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---------------------------------------------------------------- | ----- | -----------
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[Day 4: Ceres Search](https://adventofcode.com/2024/day/4) | ⭐⭐ | [![Rust](./scripts/assets/rust.png)](./2024/day4/day4.rs) [![Python](./scripts/assets/python.png)](./2024/day4/day4.py)
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[Day 5: Print Queue](https://adventofcode.com/2024/day/5) | ⭐⭐ | [![Rust](./scripts/assets/rust.png)](./2024/day5/day5.rs)
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[Day 6: Guard Gallivant](https://adventofcode.com/2024/day/6) | ⭐⭐ | [![Rust](./scripts/assets/rust.png)](./2024/day6/day6.rs)
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[Day 7: Bridge Repair](https://adventofcode.com/2024/day/7) | ⭐⭐ | [![Rust](./scripts/assets/rust.png)](./2024/day7/day7.rs) [![Python](./scripts/assets/python.png)](./2024/day7/day7.py)
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## Paste years
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Calendar | Solutions | Stars | Rust | Python
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-------- | --------- | ----- | ---- | ------
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[Advent of Code 2024](https://adventofcode.com/2024) | [Solutions](2024/README.md) | 12⭐ | 6 | 4
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[Advent of Code 2024](https://adventofcode.com/2024) | [Solutions](2024/README.md) | 14⭐ | 7 | 5
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[Advent of Code 2023](https://adventofcode.com/2023) | [Solutions](2023/README.md) | 50⭐ | 24 | 11
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[Advent of Code 2022](https://adventofcode.com/2022) | [Solutions](2022/README.md) | 50⭐ | 24 | 18
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[Advent of Code 2021](https://adventofcode.com/2021) | [Solutions](2021/README.md) | 50⭐ | 23 | 12

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