Dude, as much as I would like to help you, we do not give code out to people, instead we help you with your own code as in correction or advice.So the best thing you can do is to at least post your code by attempting to solvre your problems by yourself first, then we can help.
>i want to give a presention on functions use in code >can any one help me ,as give me these codes?
Wait. You're giving a presentation on something that you don't even know how to do?
Is that so uncommon? The idea is for him to learn how to do it so that me can make the presentation. I did that once for a speech class about 30 years ago -- made a presentation about the evils of marijuana. Didn't know a thing about it except what people had told me so I read every available book on the subject. The final presentation was a lot different than the one I thought I was going to make.
The idea of the above is that if you (the op) don't know a thing about the topic then you had better start studying. Just asking other people to give you the information without you yourself understanding the information will result in failure.