I got an amount of numbers, they are shuffled and represent the individuals. For example (3,1,3,2,5,22,5) is one individual or (22,3,1,3,5,5,2).
Mutation is done quite easy by permutation within an individual.
The problem is to find a crossover method between 2 individuals, in which the quantity of the values stay the same(for the above example 2 times 3, 2 times 5, 1 time 22 and so on).
I searched a lot on it but only found crossover methods for either unordered / ordered lists. Those for ordered lists seemed promising but they require that every value only occur ones.
Do you know a method to solve this problem or got an idea for altering an crossover for ordered list method like PMX?