Input: algorithm (FCFS, SSTF, SCAN, CSCAN, LOOK, CLOOK), the last cylinder max (cylinders 0 … max), the initial head position, the initial direction (up or down), then the request queue.
Rules:
- SSTF: nearest request next; ties → the lower cylinder.
- SCAN: serve requests in the current direction, go to the end (0 or max) only if requests remain on the other side, then reverse.
- LOOK: like SCAN, but reverse at the last request.
- CSCAN: serve in the current direction, go to the end, jump to the other end (the jump counts as head movement), and continue in the same direction.
- CLOOK: like CSCAN, but go only to the last request and jump directly to the farthest request on the other side (the jump counts).
- A request at the head's current position counts as being on the
upside.
Print Order: 53 -> 65 -> … (starting at the head) and SSTF total head movement: 236 cylinders.