For the time being `rebuild!` just applies `sort!` on each vector of the adjacency list. It should also - `union!` - check that if `j` is in the adjlist of `i`, also `i` is in the adjlist of `j`
For the time being
rebuild!just appliessort!on each vector of the adjacency list.It should also
union!jis in the adjlist ofi, alsoiis in the adjlist ofj