Function intersect_vec 

pub fn intersect_vec<'a, T: Endpoint>(
    xs: &'a RangeVec<T>,
    ys: &'a RangeVec<T>,
) -> RangeVec<T>

Constructs the intersection of two normalized vectors of ranges.

Since both arguments are guaranteed to be normalized, we can iterate over the shorter one and binary search over the longer one, which is usually a good idea.

This operation takes at most \(\mathcal{O}(\min(m + n, m \log n))\) time, where \(m\) is the size of the shorter RangeVec, and \(n\) that of the longer RangeVec.