It is basically memoized recursion. However, that does not mean that it is easy. To find out the optimal substructure - that is, building the solution to the pr

It is basically memoized recursion. However, that does not mean that it is easy. To find out the optimal substructure - that is, building the solution to the problem from the optimal solution of its subproblem decomposition - is where the actual difficulty of the technique lies. Exercises from a standard algorithm textbook like Kleinberg and Tardos should give enough practice in solving these problems. Not all of them are straightforward.