Computer Science Question Paper 2006

Guess Paper - 2006
Class - XII
Time: 3hrs M. M.: 70

All questions are compulsory
Programming Language: C++

1. Write brief answers:
a) Simplify the following Boolean expression with the help of Karnaugh Maps
(i) F(a,b,c,d)=?(0,1,3,9,10,11)
(ii) F(a,b,c)= ?(0,1,2,6)
(iii) F(a,b,c)=?(1,5,6)
(iv) F(a,b,c)=?(0,2,3,4,7) (3*4=12)

b) State the following laws and prove any one of the statements for each by truth table:
(i) Absorption Law
(ii) De Morgan’s Law
(iii) Involution Law
(iv) Distributive Law (2*4=8)

c) Define the following terms: (1*3=3)
(i) Fallacy 
(ii) Truth Table 
(iii) Maxterm

d) Solve algebraically: (2*2=4)
(a) ab + ab’c 
(b) xy’ + x’y

e) Draw the logical circuits for the following: (3*3=9)
a) (x+y’).(y’+z’) using NAND-to-NAND logic
b) (a.b.c’.d’)+(a’.c’.d)+(a.b.c.d) using NAND-to-NAND logic
c) (a.b’.c.d)+(b.c.d)+(a’.b’.c’.d’) using NOR-to-NOR logic

f) Give the product-of-sum form for the following: (1*2=2)
a) a b c F
0 0 0 0
0 0 1 1
0 1 0 1
0 1 1 0
1 0 0 0
1 0 1 0
1 1 0 1
1 1 1 1

b) a b c F
0 0 0 1
0 0 1 0
0 1 0 1
0 1 1 1
1 0 0 0
1 0 1 0
1 1 0 0
1 1 1 1

g) Give the dual of the following: (1*2=2)
a) xy’+y’z
b) a’b’c’+acd+abcd

2. Give the output of the following programs: (3*3=9)
a) #include
struct def { int i; int f;};
void main()
{
def d; d.i=1.5;
func(d);
cout< <<” “<< d.f;
}
func(def d)
{
d.f=2.5;
cout< <
}

b) #include
struct Point { int X,Y; };
void show(Point P)
{ cout< <<”:”< <
void main(){
Point U={20,10},V,W;
V=U;
V.X+=20;
W=V;
U.Y+=10;
U.X+=5;
W.X-=5;
Show(U);
Show(V);
Show(W);
}

c) #include
struct color{ char code; };
main()
{ color c={9,8};
cout<<”Code = ”<

3. Give the syntax errors in the following code programs: (3*3=9)
a) #include
struct group
{ int X1,X2;
};
void main()
{ G1, G2 group;
cin>>G1.X1<
G2=G1;
Cout< <
}

b) #include
main()
{
{
}
}

c) #include
struct { char name[12]; char destination[20]; };
void main()
{
employee e= {27,”mg”};
cout< <
}

4. Write brief answers:
a) What is the difference between structures and arrays? (2)
b) What is meant by nesting of structures? Site an example. (2)
c) What is the use of #DEFINE directive? Site an example. (1)
d) Use typedef to define unsigned int, signed int, short int. (1)

5. Write programs in C++ to perform the following: (2*3=6)
a) Accept the names and total marks of 20 students in an array. Display the names of the students (including marks) securing highest and lowest marks using structures.
b) Develop a structure to store information about employees of an organization consisting of following data elements:

Data Type Width
Code Character 6
Name Character 50
Dept Character 15
Join_date date 8

Write a program to print the names of those employees who have completed at least one year of service