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CBSE CLASS XI

Q.4. Expand UPS. 1
b) Uninterrupted Power Supply

Q.5. How many bytes are in a terabyte?
a) 1024 X 1024 X 1024 X 1024 Bytes (or) 210 X 210 X 210 X 210 Bytes (or) 24 0 Bytes

Q.6. Write the names of two popular system softwares.

a) Operating Systems: DOS, Windows XP, Unix,Solaries. Language Processors: Assembler, Compiler, Interpreter.

III. Q.1.What do you meant by a lexical unit? Give an example.

b) Token: The smallest individual unit in a program is known as a token (Lexical Unit). There are 5 types of tokens.
(i) Keywords (ii) Identifiers (iii) Literals (iv) Punctuators (v) Operators

Q.2. In each of the following cases show how the comment can be placed in a program:

i) Add a comment sum of three numbers to the statement:
sum=a+b+c;
a) sum = a+b+c; //sum of three numbers

ii)Add the comment End of Function with the ‘}’.

a) } //End of Function

Q.3. Differentiate between unions and structures with help of an example.

a) Structure: A structure is a collection of elements(variables) of different data types.
The keyword struct is used to construct a structure.
Syntax: struct structtag
{
datatype variable;
datatype variable.
-----
-----
}structure variables;
Eg: struct student
{ int rollno;
car name[26];
int m[3];
int total;
float avg;
}s1,s2;
struct s3;
Referencing Structure variables:
Structurevariable.elementname;
Eg: s1.rollno;
s2.name;
s3.marks[2];
Union : A union is a memory location that is shared by two or more different variables (generally
shared by two or more different times).
Eg: union share
{ int i;
char ch;
};
union share us;
us.i = 20;
cout<<us.ch;
At any point, you can refer to the data stored in a us as either an
integer or a character.
Difference between a union and a structure:
A union is a memory location that is shared by two or more different variables.
A structure have separate memory location for every variable.
In the above example for structure variable S1, 40 Bytes will be reserved and
For union variable us, 2 bytes will be reserved.

Paper By Mr. Ravi Kiran
Email Id :[email protected]