algorist

Helper tools, algorithms and data structures for competitive programming.

Algorist is both a CLI tool for managing programming contest projects AND a collection of useful algorithms and data structures to use in those projects.

Installation

The crate provides cargo sub-command algorist, which can be installed using:

cargo install algorist

Once installed, you can use it as cargo algorist.

Usage

The algorist CLI tool provides a way to create a new contest project, which is a normal Rust project, use additional modules with common algorithms and data structures, and then bundle each problem into a single output file that can be submitted to the contest system.

Create a new contest project

To create a new contest project:

cargo algorist create <contest_id>

# examples:
cargo algorist create 4545
cargo algorist create contests/4545 # sub-folders are supported

This will create a Rust project with all the necessary problem files and algorithm modules copied into it.

Problem files will be created in src/bin directory, and the library with algorithms and data structures will be created in src/algorist module.

# run problem A (`src/bin/a.rs`)
# it expects input from stdin
cargo run --bin a

# it is a normal Rust project, you can use all the usual commands
cargo build
cargo test

If you don't want to have initial problem files, you can create a new contest project with --empty flag:

cargo algorist create <contest_id> --empty

Later on, you can always add a problem file into src/bin directory, using:

cargo algorist add <problem_id>

# examples:
cargo algorist add a        # `.rs` is not required
cargo algorist add a.rs     # same as above

Work on a problem

All problems are located in src/bin/<problem_id>.rs files. The file will contain entry point main function, which is expected to read input from standard input and write output to standard output.

The starter code for the problem file will look something like this:

use algorist::io::{test_cases, wln};

fn main() {
    test_cases(&mut |scan, w| {
        let (a, b) = scan.u2();
        wln!(w, "{}", a + b);
    });
}

See the documentation on io module (and other provided algorithms and data structures) for more details on the default code provided in problem files.

Normally, when working on solution, you copy the tests cases from the contest system into the clipboard (or file), and then need to see the output of your program:

# alias pbpaste=’xsel — clipboard — output’ on Linux
pbpaste | cargo run --bin <problem_id>   # gets input from clipboard
cargo run --bin <problem_id> < input.txt # gets input from file

Once you are happy with the output, you can submit the solution back to the contest system (by bundling into a single file).

Bundle the project

Contest systems expect a single output file, where all used modules are packed within the scope of that file. At the very least io module is expected to be included in the output file.

cargo algorist bundle <problem_id>

# examples:
cargo algorist bundle a # `.rs` is not required
cargo algorist bundle a.rs

This will create a single output file in bundled/<problem_id>.rs file, which can be submitted to the contest system.

Only the modules actually used in the problem file will be included in the output file.

Included algorithms and data structures

The Algorist is also a library of algorithms and data structures, which will be copied into your contest project, and can be used in your problem files.

See algorist module documentation for a complete list of available algorithms and data structures, as well as their usage examples.

License

MIT