ef_rs 0.1.0

A Rust implementation of the Elias-Fano encoding scheme
Documentation 
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# Elias-Fano Encoding in Rust

[![Build Status](https://github.com/pisa-engine/ef_rs/workflows/Rust%20CI/badge.svg)](https://github.com/pisa-engine/ef_rs/actions)
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[![Documentation](https://docs.rs/ef_rs/badge.svg)](https://docs.rs/ef_rs)
[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)

A Rust implementation of the Elias-Fano encoding scheme for storing monotonic sequences of integers efficiently.

## Features

- Efficient storage of monotonic sequences
- O(1) access to elements
- Support for duplicate values
- Builder pattern for incremental construction
- Iterator support
- Serialization/deserialization support via serde
- No unsafe code

## Usage

Add this to your `Cargo.toml`:

```toml
[dependencies]
ef_rs = "0.1.0"
```

Basic example:

```rust
use ef_rs::elias_fano::EliasFano;

// Create from a sorted sequence
let values = vec![2, 5, 5, 9];
let seq = EliasFano::from(&values);

// Access elements
assert_eq!(seq.get(0), Some(2));
assert_eq!(seq.get(1), Some(5));
assert_eq!(seq.get(2), Some(5));
assert_eq!(seq.get(3), Some(9));

// Iterate over values
let collected: Vec<_> = seq.iter().collect();
assert_eq!(collected, values);
```

Using the builder pattern:

```rust
use ef_rs::elias_fano::EliasFanoBuilder;

let mut builder = EliasFanoBuilder::new(10, 4);  // universe=10, count=4
builder.add(2);
builder.add(5);
builder.add(5);
builder.add(9);
let seq = builder.finalize();

assert_eq!(seq.get(0), Some(2));
assert_eq!(seq.get(1), Some(5));
assert_eq!(seq.get(2), Some(5));
assert_eq!(seq.get(3), Some(9));
```

## Performance

The structure provides O(1) access to elements while using approximately
2n + log(u/n) bits of space, where n is the number of elements and u is
the universe size (maximum value + 1).

## Documentation

For detailed documentation, visit [docs.rs](https://docs.rs/ef_rs).

## Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

## License

This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details.