pub fn lll_reduce_bigint(basis: &[Vec<BigInt>]) -> Vec<Vec<BigInt>>Expand description
LLL-reduce a BigInt lattice basis — the entry point for lattices with huge entries, such as the
N^m-scaled rows of Coppersmith’s method. The symmetry that makes this fast: only the BASIS need be
exact; the Gram–Schmidt that steers the size-reductions and Lovász swaps runs in floating point, so
there is no rational coefficient blow-up. The reduced basis is still exact integer, and correctness is
re-checked downstream (a Coppersmith root either divides N or it does not).