Tarjan SCC
Push on entry, lower low-links through open vertices, pop a whole component when low[u] == disc[u].
Decision · step 5 of 24Bridges and Components: Tarjan on two cycles
Edge 2 -> 0: 0 is still on the stack, so it is open and in the same component as 2. low[2] drops to disc[0] = 0.
What you will see
Each vertex shows index/low; the stack beside the graph pops a whole component at once.
Cost
| Best | O(V + E) |
|---|---|
| Average | O(V + E) |
| Worst | O(V + E) |
| Space | O(V) |
How you work with it here
play it through, step one change at a time, scrub to any step, run it on your own input, predict what happens next.
Screen readers: Vertices announce name, discovery numbers where relevant and component; each step announces the structural conclusion (bridge found, component closed).
Reduced motion: Component colouring and ordering changes crossfade in place.
Before this
Taught by the same lesson
Bridges and Components covers these too, in the same run.