Build your Floyd-Warshall skills with these problems:
Shortest Routes II (CSES): all-pairs queries, direct Floyd-Warshall application.
Find the City (LeetCode ): threshold-based counting, post-processing the distance matrix.
Course Schedule IV (LeetCode ): transitive closure variant using boolean Floyd-Warshall.
Each problem reinforces a different aspect. CSES tests basic usage, LeetCode tests filtering results, and LeetCode tests the reachability variant.