Figure 1
From: Steiner tree methods for optimal sub-network identification: an empirical study
Illustration of the shortest paths heuristic: The algorithm starts with an arbitrarily picked terminal a (left). Then the terminal (f) closest to a is picked and the shortest paths connecting a to f added to the temporary Steiner tree G′ (middle). The algorithm proceeds by finding the terminal (g) closest to all nodes in G’. Accordingly, the shortest path from f to g is added to G′ (right).