Computer Scienc...

Consider three processes P1, P2 and P3 with arrival time of 0,1 and 2 time units respectively, and  total execution time of 20, 30 and 40 units respectively. Each process spends the first 30% of execution time doing I/O, then next 60% doing CPU and remaining 10% time doing I/O again. The operating uses a First come first serve scheduling algorithm and schedules a new process either when the running process gets blocked on I/O or when the running process finishes its compute burst. For what percentage of time does the CPU remain idle?

NOTE:
Ideal time at the start and at the end is counted.

Suppose that a code has the following four valid codewords:

11001100

00110011

11111111

00000000

What is the maximum number of errors that can be detected for this code?

Consider the below given code

#include<stdio.h>

int main()

{

int k, i = 1;

while(i < k)

i = i * 3;

}

The number of times while loop runs is _____.

A system uses 3 physical page frames which are initially empty. What is the absolute difference between the no. of page faults using the Least recently used(LRU) and Most recently used(MRU) page replacement policies while processing the page reference string given below ?

7, 0, 1, 2, 0, 3, 0, 4, 2, 3, 0, 3, 2, 1, 2, 0, 1, 7, 0, 1

If there are m input lines and n output lines for a decoder that is used to uniquely address a byte addressable 4 KB RAM, then the minimum value of m + n is ______.

Consider the following two sets of LR(1) items of an LR(1) grammar.

Which of the following statements related to merging of the two sets in the corresponding LALR

parser is/are FALSE?

1. Cannot be merged since look aheads are different.

2. Can be merged but will result in S-R conflict.

3. Can be merged but will result in R-R conflict.

4. Cannot be merged since goto on c will lead to two different sets.

Let x be the value of a counting semaphore at a particular time of computation. 14 signal operation 23 wait operation is performed on the counting semaphore variable. If resulting value of the semaphore is -3 then the value of x is ________.

The number of substrings that can be formed from string given by “ABCDEFGH.....Z” is

The POST-order traversal of a binary search tree is given by 117, 126, 108, 131, 157, 182, 163, 148, 195 and 129. Then the PRE-order traversal of this tree is: