Credit: University of Copenhagen
One of the most classic algorithmic problems deals with calculating the shortest path between two points. A more complicated variant of the problem is when the route traverses a changing network--whether this be a road network or the internet. For 40 years, an algorithm has been sought to provide an optimal solution to this problem. Now, computer scientist Christian Wulff-Nilsen of the University of Copenhagen and two research colleagues have come up with a recipe.
When heading somewhere new, most of us leave it to computer algorithms to help us find the best route, whether by using a car's GPS, or public transport and map apps on their phone. Still, there are times when a proposed route doesn't quite align with reality. This is because road networks, public transportation networks and other networks aren't static. The best route can suddenly be the slowest, e.g. because a queue has formed due to roadworks or an accident.