Function first_ve_degree_zagreb_beta 

pub fn first_ve_degree_zagreb_beta(graph: &Graph) -> IgraphResult<u64>

Compute the first ve-degree Zagreb beta index.

M₁^{βve}(G) = Σ_{(u,v)∈E} [d_{ve}(u) + d_{ve}(v)]

Self-loops are skipped.

Examples

use rust_igraph::{Graph, first_ve_degree_zagreb_beta};

// K_3: d_ve=[4,4,4], 3 edges × (4+4) = 24
let g = Graph::from_edges(&[(0,1),(1,2),(0,2)], false, Some(3)).unwrap();
assert_eq!(first_ve_degree_zagreb_beta(&g).unwrap(), 24);