You might find the following two articles helpful:

Cultured Perl: Genetic Algorithms With Perl

Genetic Algorithms With Perl

Your question wasn't very clear, but if I understood, you want to make sure that each element is unique in the set resulting from recombination. How about just keeping an ordered array containing all of the 100 possible values that a randomly selected element could take, and as you use each one during recombination, set the array element to undef. Then just test to see if the array element is defined before you use it....