Generator is a module which generates combinations and permutations
It's very easy !! Generator instances are created that are either Combinations or Permutations using statics methods in Generators class, newCombination or newPermutation as follows:
Genetator<Integer> combination = Generators.newCombination(1, 2, 3);
final List<List<Integer>> listOfCombinationGenerateToList = combination.generate(2);The above code creates combinations of 2 elements from the set {1, 2, 3}, and returns the result as a list.
Genetator<String> permutation = Generators.newPermutation("A", "B", "C", "A");
final List<String> listOfPermutationGenerateToWord = combination.generateToWord(3);The above code creates permutations of 3 elements from the set {"A", "B", "C", "D"}, and returns the result as a list of String.
You can use generateToWord by specifying a letter separator as follows.
final List<String> listOfPermutationGenerateToWord = combination.generateToWord(3, '_');The separator is of type char, for a list L = [A, B, C], we will have the following output A_B_C.
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