zrx-graph 0.0.13

// Copyright (c) 2025-2026 Zensical and contributors

// SPDX-License-Identifier: MIT
// All contributions are certified under the DCO

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// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
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// furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included in
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// ----------------------------------------------------------------------------

//! Reachability.

use super::adjacency::Adjacency;

mod distance;

use distance::Distance;

// ----------------------------------------------------------------------------
// Structs
// ----------------------------------------------------------------------------

/// Direct reachability.
#[derive(Debug)]
pub struct Direct;

// ----------------------------------------------------------------------------

/// Transitive reachability.
#[derive(Debug)]
pub struct Transitive {
    /// Distance matrix.
    distance: Distance,
}

// ----------------------------------------------------------------------------
// Implementations
// ----------------------------------------------------------------------------

impl Transitive {
    /// Creates transitive reachability from the given adjacency list.
    #[must_use]
    pub fn new(adj: &Adjacency) -> Self {
        Self { distance: Distance::new(adj) }
    }

    /// Returns whether there is a path from the source to the target.
    #[inline]
    #[must_use]
    pub fn has_path(&self, source: usize, target: usize) -> bool {
        self.distance.has_path(source, target)
    }
}