I discovered a great website that comprehensively covers puzzles and questions in C language.
Gowrikumar.com – C Puzzles
What’s special about these puzzles and questions is that some of these questions are asked in interviews of experienced C programmers at Multi National Companies. The standard of the questions and answers at the above site is pretty high, usually suits programmers with prior experience or expertise in C.
The man behind this website is CH. Gowri Kumar. He is from Hyderabad-India. He is a masters graduate from Indian Institute of science and has over 7 years of Software development experience with top IT companies such as HP, Motorola, Microsoft etc.
If you are a C lover, be sure to subscribe to the Google group, Programming Puzzles maintained by Gowrikumar himself. You can get all your C programming questions solved by the vibrant and active community there.
Comment below if you know sites similar to these which cover C programs.
About the Author: Sridhar Jammalamadaka is the Editor of Interview Mantra. He's a typically non-typical Software Engineer from Pune, India. He likes entrepreneurship, web technologies and Micro Controller programming. He enjoys playing cricket and piano (but rarely does these activities). Through this website, he wishes to gather a large community of aspiring engineers, entrepreneurs and professionals from all parts of the globe. You can connect with him on Facebook - http://www.facebook.com/sridhar.j 
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