Please help, this code has dissapointed me

[fabunmi]

please i need an idea of how to prevent duplication,i wrote a code to read from text file and store in an array and also to do random selection on the array element using the index but later, that was achieved but i used hash set to remove duplicate bot it is not working, what can i do

[m00nchile]

Random selection is achieved easier on structures that store elements based on index. One such structure is Vector, look through the API for it, and you'll also find a nifty little method that can prevent duplicaton. I'd also suggest that in the future, try to be clearer about what you are doing and what you need help with. Also, have a look at this:
The Short, Self Contained, Correct (Compilable), Example or SSCCE (taken from Fubarables sig).
Posting an SSCCE of what you are trying to acomplish will make your question more understandable, and people will be more eager to answer.