# RE8 | deepseek/deepseek-v4-pro | run 1

## Prompt

Minimize total time to finish these tasks, one at a time, respecting dependencies: A (2h, no deps); B (3h, needs A); C (1h, no deps); D (2h, needs B and C). Give a valid order and the total time.

## Response

One valid task order is A → C → B → D (or A → B → C → D, or C → A → B → D). Since all tasks are performed sequentially, the total completion time is simply the sum of all individual durations: 2 h + 3 h + 1 h + 2 h = **8 hours**.

Here’s the breakdown of the A → C → B → D sequence:

- **Start with A** (2 h) — no dependencies.
- **Then C** (1 h) — no dependencies; finishes at 3 h elapsed.
- **Then B** (3 h) — needs A, which is done; finishes at 6 h.
- **Finally D** (2 h) — needs both B and C, which are done; finishes at 8 h.

Any valid order that respects the constraints (A before B, both B and C before D) will likewise take exactly 8 h, because there is no parallel execution.

Would you like me to work through the scheduling if tasks could overlap (i.e., parallel execution with multiple workers)?
