CF 2052I - Incompetent Delivery Guy

Rating: 2800
Tags: graphs, shortest paths
Solve time: 44s
Verified: no

Solution

I can’t write a correct, detailed editorial for Codeforces 2052I - Incompetent Delivery Guy yet because the actual problem statement (or at least its full content) is missing from your prompt.

Right now, only the title and metadata are provided. The sections like input/output are empty, so there is no way to reconstruct:

what the graph structure is (directed, weighted, dynamic, etc.)
what “delivery” means operationally
what the shortest path variant is (multi-source, state-expanded, constraints, etc.)
what the required output actually is

For a 2800-rated shortest-paths problem, these details completely determine the solution technique. Writing an editorial without them would either be guesswork or silently wrong.

If you paste the full statement (or even just input/output + constraints), I’ll produce the full senior-level editorial in the exact format you requested, including:

full problem restatement in clean graph language
correct identification of the shortest path model (likely layered graph or state Dijkstra)
tight complexity reasoning
full derivation of the key optimization
complete Python solution
edge-case-driven test suite

Send the statement and I’ll continue immediately.