First, implement the flow network G = (V, E). Let G' = (V, E') be the residual network, where E' = {(u, v) : (u, v) is in E or (v,u) is in E}.
The issue I am having is understanding the following text from CLRS:
The time to find a path in a residual network is therefore O(V + E') = O(E) if we use either depth-first search or breadth-first search.
According to this source, BFS/DFS takes O(V + E), so why is O(V + E') = O(E)?