Hamid-World

Question:-1
Write algorithms and draw a corresponding flow chars to conver a decimal number to its
i- Binary equivalent.
ii- Octal equivalent.

Ans:-
i) // Algorithm : Decimal to binary
start
1.let num be an array of integer
2.input no.
3.let rem=0,ctr=0
4.while(rem!=1)
begin
q=no/2
rem=no mod 2
num[ctr]=rem
ctr++
no=q
end
5.while(ctr>=0)
begin
print num[ctr]
ctr=ctr-1
end
end

//Shell program : Decimal to binary
clear
echo "Enter a No."
read n
b=" "
whil [$n-ne 0]
do b='expr $n %2'b
n='expr $n/2'
done
echo "Binary of $n=$b"

Flow chart unsolved.

ii) // Algorithm : Decimal to Octal
start
1.let num be an array of integer
2.input no.
3.let rem=0,ctr=0
4.while(rem!=1)
begin
q=no/8
rem=no mod 8
num[ctr]=rem
ctr++
no=q
end
5.while(ctr>=0)
begin
print num[ctr]
ctr=ctr-1
end
end

//Shell program : Decimal to Octal
clear
echo "Enter a No."
read n
o=" "
whil [$n-ne 0]
do o='expr $n %2'o
n='expr $n/8'
done
echo "Binary of $n=$o"

Flow chart unsolved.



Question :- 2
Consider the following set of processes that arrive in the ready queue at the same time:
Process CPU time
P1 5
P2 6
P3 3
P4 7
P5 1
Consider the following scheduling algorithms:
First Come First Serve (FCFS), Shortest job first(SJF) and Round Robin (quantum=1)
-- What is the turnaround time of each process for each of the above scheduling algorithms? Also find the average turnaround time.
-- What is the waiting time of each process for each of the above scheduling algorithms? Also, find the average waiting time.

Ans:-

i) Turnaround Time = 65
Average Turnaround Time = 65/5 = 13
ii) Waiting time = 47
Average Waiting Time = 47/5 = 9.4





Question:-3
Summarize the important features of LINUX operating system. Justify, how it is more advanced than earlier UNIX operating systems?

Ans:-
i) Linux is technically advanced:
It's technically superior to many other OS'es, like the infamous Redmond OS.
ii) Linux is highly configurable :
You can customize Linux exactly to your liking. You can make it work exactly the way you want, and on the plateform you want. You can also optimize your Linux system for your very own hardware, so you can run Linux faster and get every drops of performance squeezed out of your box.
iii)Linux is secure :
Linux has many advanced features that protect your system from both intrures (like vires etc.) and stupid users.
iv) Software dependencies:
Software dependencies is an excellent thing because it helps you keep things small and simple.

Unix requires a more powerful hardware configuration. It will work in large mainframe computers but will not work in an x86 based personal computer. Linux however, has small hardware requirements and it will work on both a large mainframe computer and an x86 based personal computer.



Question:-4
Write a shell programs for the following :
i- Greatest common Divisor (GCD) of the given three numbers.
ii- To check whether the given number is an Avogadro number or not.

Ans:-
i) Unsolved
ii)
//To check whether the given number is an Avogadro number or not.
1. Set 0 to S,R
2. Input Num
3. Initialize T with Num
4. Repeat steps 5 to 7 until T>0
5. R=T mod 10
6. S=S+(R*R*R)
7. T=T/10
8. If S=Num then print "Avogadro Number" else
9. End



Question:-5
Derive a regula grammer to describe the syntax of any two looping constructs of C programming language.

Ans:-
i)
For loop of C language :
::=for(exp1;exp2;exp3)
start symbol::=
Terminal::=
Non terminal::=
::=>stmt>op
::=<=|>|:=|=
::=[a....b][A-Z][0-9]

ii)
While loop of C language:
::=whileend while
start symbol::=
::=op
::=<|>|!=|<>|
::=[a...b]|[A-Z]|[0-9]
::=$$| || |!



Question:-6
List and execute the following UNIX commands
(a) To change the Password.
Ans- passwd
(b) To search the files in the current directiory/subdirectory for lines that matches a particular string pattern give.
Ans- grep "string"
(c) To print first 5 lines of a file.
Ans- head [-5]
(d) To print the number of processes run by a particular user.
Ans- ps -au
(e) To kill a process which is running in the background.
Ans- kill
(f) To display the number of blank spaces in a given file.
Ans-
vi file name
:[on colon prompt] issue the following command
:set list on
Tabs will be displayed as ^I
Line feed will be displayed as $
(g) To sort alphabetically, a list of numbers stores in a data file in an ascending order.
Ans- sort -rn
(h) To convert the upper case letter to corresponding lower case letter's in a text file.
Ans- tr '[A-Z]' '[a-z]'
(i) To cound the number of users currently logged on.
Ans- who | wc-1
(j) To display the calender for a given month and year.
Ans- cal 'date "+%m +%y"'