Function clique_cover_number 

pub fn clique_cover_number(graph: &Graph) -> IgraphResult<u32>

Compute the clique cover number θ(G).

The minimum number of cliques needed to cover all vertices. Uses brute-force search — only feasible for small graphs.

Examples

use rust_igraph::{Graph, clique_cover_number};

// K_3 + K_2: need exactly 2 cliques
let g = Graph::from_edges(
    &[(0,1),(0,2),(1,2),(3,4)], false, Some(5)
).unwrap();
assert_eq!(clique_cover_number(&g).unwrap(), 2);