# GATE | GATE-CS-2016 (Set 1) | Question 58

• Difficulty Level : Easy
• Last Updated : 27 Nov, 2018

Consider a disk queue with requests for I/O to blocks on cylinders 47, 38, 121, 191, 87, 11, 92, 10. The C-LOOK scheduling algorithm is used. The head is initially at cylinder number 63, moving towards larger cylinder numbers on its servicing pass. The cylinders are numbered from 0 to 199. The total head movement (in number of cylinders) incurred while servicing these requests is:

Note : This question was asked as Numerical Answer Type.

Attention reader! Don’t stop learning now.  Practice GATE exam well before the actual exam with the subject-wise and overall quizzes available in GATE Test Series Course.

Learn all GATE CS concepts with Free Live Classes on our youtube channel.

(A) 346
(B) 165
(C) 154
(D) 173

Explanation: The head movement would be:

```63 => 87 24 movements
87 => 92 5 movements
92 => 121 29 movements
121 => 191 70 movements
191 --> 10 181 movement
10 => 11 1 movement
11 => 38 27 movements
38 => 47 9 movements ```

Total head movements = 346

So, option (A) is correct.

Quiz of this Question

My Personal Notes arrow_drop_up