Santa & Nexis
Nexis Nexis
Hey Santa, I've been crunching numbers on your delivery routes and think there's a way to cut your journey time—interested in a quick algorithm rundown?
Santa Santa
Ho ho ho! That sounds exciting, I'm all ears for your brilliant ideas, do share!
Nexis Nexis
Use a weighted graph of stops, run Dijkstra from the depot each night; add a penalty for routes that intersect previously visited paths that night to avoid overlap, and schedule stops in batches so each truck does a closed loop that ends back at the depot. That reduces idle time and guarantees a 12‑hour maximum.
Santa Santa
Wow, that’s a clever idea! A weighted graph with Dijkstra sounds like a good way to find the fastest paths. I love the thought of keeping trucks looping back to the depot—less wandering and more time for gifts. Can you show me a sample route plan so I can see how it works in practice? Thank you!
Nexis Nexis
Here’s a minimal sketch in Python – no GUI, just raw data. ```python # nodes are stops, 0 is the depot edges = { 0: [(1,2),(2,4),(3,7)], 1: [(0,2),(2,1),(4,5)], 2: [(0,4),(1,1),(3,3),(4,2)], 3: [(0,7),(2,3),(4,6)], 4: [(1,5),(2,2),(3,6),(0,8)] } def dijkstra(start): import heapq dist = {n: float('inf') for n in edges} dist[start] = 0 pq = [(0,start)] while pq: d,u = heapq.heappop(pq) if d!=dist[u]: continue for v,w in edges[u]: if d+w < dist[v]: dist[v] = d+w heapq.heappush(pq,(dist[v],v)) return dist # get shortest round‑trip from depot dist = dijkstra(0) route = sorted(dist.items(), key=lambda x: x[1]) # just a naive batch print(route) ``` Run it, tweak the weights, and you get a quick list of where each truck should go. Remember to add a small penalty for overlapping edges if you want to keep routes separate. That’s it, no fancy GUI needed.
Santa Santa
That looks fantastic, thank you! I’ll load it up and start testing – looking forward to seeing the routes light up and making sure every child gets their gifts on time!