“…In particular, that allows simple 'visual' implementation of o heuristic algorithms [4,5,28] o nondeterministic algorithms [29] o randomized algorithms [30] • The programmer can define the solution scope, that is, how many solutions will be found (if they exist) -a single solution, a fixed in advance number of solutions, all solutions, prompting after each solution if another solution should be sought. For example, the recognizer of arithmetic expressions (Fig.…”