linking 2 classes using interfaces

Sir, in the class we have discussed about linking classes with interfaces..

i googled for it a long time, but i didn't find solution for that..

Finally i have posted it in dreamincode.net (a programmers website)..

The experties responded in this way

(click the link for more details).....

http://www.dreamincode.net/forums/topic/245891-linking-with-interfaces/