lunaris_engine 0.1.0

A collection of efficient algorithms implemented in Rust for real-world projects.
Documentation 
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//! Flood Fill (Generic, Production-Grade)
//!
//! Performs a flood fill on a 2D grid.
//!
//! # Type Parameters
//! * `T`: Value type. Must implement `Clone` + `PartialEq`.
//!
//! # Example
//! ```rust
//! use lunaris_engine::matrix::flood_fill::*;
//! let mut grid = vec![vec![1,1,1], vec![1,1,0], vec![1,0,1]];
//! flood_fill(&mut grid, 1, 1, 2);
//! assert_eq!(grid[1][1], 2);
//! ```
pub fn flood_fill<T: Clone + PartialEq>(grid: &mut Vec<Vec<T>>, sr: usize, sc: usize, new_val: T) {
    let rows = grid.len();
    let cols = if rows > 0 { grid[0].len() } else { 0 };
    let orig = grid[sr][sc].clone();
    if orig == new_val {
        return;
    }
    fn dfs<T: Clone + PartialEq>(
        grid: &mut Vec<Vec<T>>,
        r: usize,
        c: usize,
        orig: &T,
        new_val: &T,
        rows: usize,
        cols: usize,
    ) {
        if r >= rows || c >= cols || grid[r][c] != *orig {
            return;
        }
        grid[r][c] = new_val.clone();
        if r > 0 {
            dfs(grid, r - 1, c, orig, new_val, rows, cols);
        }
        if c > 0 {
            dfs(grid, r, c - 1, orig, new_val, rows, cols);
        }
        if r + 1 < rows {
            dfs(grid, r + 1, c, orig, new_val, rows, cols);
        }
        if c + 1 < cols {
            dfs(grid, r, c + 1, orig, new_val, rows, cols);
        }
    }
    dfs(grid, sr, sc, &orig, &new_val, rows, cols);
}