Which class of algorithms would this sort of a problem belong to? If I had to pick up a book on algorithms, which topic should I be looking at to find more problems of this nature and their explanation?

*Given the current location on of the horse (or whatever the thing is that moves two spaces horizontally and one vertically) on a chess board, say, (x1, y1), how many steps would you need to move it to reach a destination location (x2, y2)?*

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This would be a pathfinding algorithm which would be part of graph theory.

Example algorithms include A* and Dijkstra’s algorithm.