How to enhance my skills as a programmer I want to learn Cryptography and so I am interested to master C-programming.

I know the basic concepts of C-programming  like how to use an array,pointers etc.

I want to develop myself so that I can find the different loopholes in the security of different cryptosystems.

Basically I want to work in Attacking of Cryptosystems apart from developing my skills in theory.

Will someone suggest me some goods or a list of books(say) which are just above the beginner's level and which will establish me as a good programmer?

I will be extremely thankful if someone could help.
You don't need books. You need to write lots of programs. Since you are interested in cryptography, you should practice writing programs that involve mathematics. A good way to do so is to join Project Euler and just go down the list. Good luck!