Lattice Reduction <p>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?</p> <p>Also is there very simple C or C++-implementation of the <a href="http://mathworld.wolfram.com/LLLAlgorithm.html" rel="nofollow">LLL algorithm</a>?</p>