Union of ALL shortest paths between two nodes (review 9.17: the
singular findShortestPath made "Find paths to here" a one-path
demo by construction). Layered BFS from the source records each
node's distance; an edge belongs to the union iff it steps from
distance d to d+1 along some shortest route, collected by walking
backward from the target through distance-decreasing edges. The
result is the SUBGRAPH of shortest routes (nodeIds/edgeIds), plus
the route count (capped: counts can be exponential in dense
graphs; the cap keeps the label honest as "50+").
Union of ALL shortest paths between two nodes (review 9.17: the singular findShortestPath made "Find paths to here" a one-path demo by construction). Layered BFS from the source records each node's distance; an edge belongs to the union iff it steps from distance d to d+1 along some shortest route, collected by walking backward from the target through distance-decreasing edges. The result is the SUBGRAPH of shortest routes (nodeIds/edgeIds), plus the route count (capped: counts can be exponential in dense graphs; the cap keeps the label honest as "50+").