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shahabz_siddiqui
i don't know how to solve problems ....actually i know the all rules, syntax and how to write in scheme.....but i can not solve the problems that teachers assign me....
It takes some time to get there. What works for me is that I try to break down bigger problems into sub-problems and solve those one by one. And think a lot, try different approaches, etc. And also, practice a lot.
There's a Lisp book primarily concerned with solving problems. It is called How To Design Programs and is freely available at http://htdp.org. Give that book a chance. Since you know Lisp quite well, you can begin at a later chapter --- for example, chapter 9.