You could do this a lot of different ways.
Let's say you have a couple of very large arrays.
Like Harggood said, i would have 2 arrays.(Think of this as a seperate program then the main one, call it "the editor")
You have array(1) inputting the questions.. so you would type, Hello
This would be stored into array(1)
Right after that you have array(2) inputting the answers... so you would type, Hello, my name is computer or whatever
Once your done completing all of your arrays run through a for next loop and upper$ them(Capitalize all of the questions and answers), you save them to a text file, thus looking something like this
Answersquestions.txt
Hello
Hello, my name is computer
After your done writing that program, you make the actual "AI" program. You load in your text file into arrays.. then when the person types in hello, you compare that to your array. If it's found, you mark the array number, then load in the answer.
One of the problems you'll encounter is the person typing in something different, or spelt wrong. In this case the only thing you can do is perhaps have random messages in this case.
Ie Question. What is your naem
Ie Answer. People really do like me you know.
Obviously, the more questions and answers you add to the list will lower the posibility of people making mistakes and not getting the answer you want to give them.
Hope this provides a little bit of help.
- Merix