The program works correctly and it works quickly for small input files: tinyG.txt and tinyT.txt.

But for sample files: largeG.txt and largeT.txt (1000000 numbers in each), it takes an unacceptably long time.

Improvement

• Add a static rank function, brank to MStd that uses binary search.
• Modify the filter program to sort the vector v and use MStd::brank instead of MStd::lrank.