Benchmark Contest:Count character ratio in DNA file

RULES:
The program must count(without prior knowledge of file beyond its format) GC-content of source file.
GC-content is fraction of GC vs AT chars found in the file expressed as floating point number. http://en.wikipedia.org/wiki/GC-content
source file https://github.com/dubst3pp4/GC-Content-OOC/blob/master/Homo_sapiens.GRCh37.67.dna_rm.chromosome.Y.fa

>>15 28Mcycles with precomputed tables. Its less flexible though.
>>16 http://bbs.progrider.org/prog/read/1423332691/4 -> http://codepad.org/VONAd6J5 it segfaults(i think he attempted to cleverly use the stack to print a string with a function pointer)