Floyd–Warshall algorithm

In a world of points and lines so neat, A map of paths where edges meet, Floyd and Warshall found a way, To trace the shortest path each day. Start with a table, distances defined, Infinity for those we cannot find, Zero marks where each point stands, The journey begins with careful hands. Through each point, a detour we try, Is there a shorter way to fly? Check the middle, check the round, A quicker route might yet be found. Update the table, step by step, No need for haste, no need to fret, From A to B, and C to D, All paths clear as they can be. But beware the loops that spin, Negative cycles drawing in, If a path turns back too soon, The map reveals a darker tune. When all is done, the map is clear, Shortest paths both far and near, Floyd and Warshall’s work is done, Every route beneath the sun.