I have two matrices A and B with same number of rows. Consider a Lattice generated by the rows of B. I want to reduce B and during the reduction change A accordingly. That is if i-th row and j-th row of B interchanges, need to sweep i-th row and j-th row of A also, similarly other elementary row operations. How can I do these?
Also is there very simple C or C++-implementation of the LLL algorithm?