Can Contraction Hierarchies handle dynamic graphs like traffic or road closure?
Precomputation is offline and static. Dynamic real-world queries multiply the precomputed distance by current-edge weights (traffic). Major closures require local re-contraction or a hybrid approach; most systems precompute once per week or on infrastructure change.
Answered in
Why Google Maps Computes Shortcuts OfflineContraction Hierarchies precomputes shortcut edges offline so routing queries skip neighbourhood streets and touch only 2,000 nodes in under 10 milliseconds.
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