Function kosaraju_scc 

pub fn kosaraju_scc<G>(graph: &G) -> Vec<Vec<NodeId>>
where
    G: Graph<Weight = f64>,

Finds all Strongly Connected Components (SCCs) using Kosaraju’s algorithm.

Kosaraju’s algorithm uses two DFS passes:

1. Run DFS on the original graph, recording nodes in finish order.
2. Run DFS on the transposed graph in reverse finish order — each DFS tree in this pass is one SCC.

Returns

A Vec of SCCs, each SCC being a Vec<NodeId>. SCCs are returned in topological order of the condensed DAG (the first SCC has no incoming edges from other SCCs in the condensed graph).

Complexity

O(V + E) — two DFS passes plus one graph transposition.

Examples

use graph_core::{AdjacencyList, Graph};
use graph_advanced::kosaraju_scc;

// 0 → 1 → 0  (cycle),  1 → 2  (singleton)
let mut g: AdjacencyList<()> = AdjacencyList::directed();
let n: Vec<_> = (0..3).map(|_| g.add_node(())).collect();
g.add_edge(n[0], n[1], 1.0).unwrap();
g.add_edge(n[1], n[0], 1.0).unwrap();
g.add_edge(n[1], n[2], 1.0).unwrap();

let sccs = kosaraju_scc(&g);
assert_eq!(sccs.len(), 2);