Google Code-in

Error handling is extremely important but is missing at many crucial places. Your task it to find those places, and handle errors appropriately. You have some helpful functions already, such as fatal() (see: https://github.com/saurabhshri/CCAligner/blob/master/src/lib_ccaligner/commons.cpp) built in to aid in this, but you may add more for your convenience. Run the programs and test all cases for the error you handle. We expect a well furnished pull request with good documentation (code comments, good function names, good error messages etc.).