Interview Questions on C - Data types
1. What is Datatype and what are all the Data type exist in C language?
Definition :- Datatype refers that particular variable or function belongs to particular type.
Mainly There are two data types exist in C language
1. Basic datatypes
Type Storage size Value range
Char 1 byte -128 to 127 or 0 to 255
Int 2 bytes -32,768 to 32,767 or -
Long 4 bytes -2,147,483,648 to 2,147,483,647
Float 4 byte
Double 8 bytes
2. How to initialize char value?
Cahr ch= ‘f’; (value enclosed with sigle quotes)
3. When we use void type?
Basically void type specifies no value is available.
It is used in 3 kinds of situations
1. Use return type as void :- if fumction does not return any value. Then we can return void.
2. Pass void as argument :- if function does not accept any arguments. Then we can pass void as argument.
3. Pointers to viod :- A pointer of type void * represents the address of an object,
4. What is the size of void pointer?
2 bytes(any data type has size of 2 bytes).
5. What is variable and how to declare a Variable in C?
Def :- Variable is name of memory location
Syntax :-
type variable_name = value;
Ex:-
int d = 3, f = 5;
6. What is lvalue and rvalue?
Expressions that refer to a memory location is called "lvalue"
Most likely Lvalue exist left hand side express ion of ‘=’ operator
The term rvalue refers to a data value that is stored at some address in memory.
Mostly Rvalue is at right hand side operator of ‘=’ operator
Ex :– a=5;
Here a is lvalue
5 is r value.
7. What is Constant Variable?
Def:- The Variable Which cannot be changed the value during program execution.
8. How to define Constant Values?
There are two simple ways in C to define constants:
1. Using #define preprocessor.
#define identifier value
2. Using const keyword.
const type variable = value;
9. How to print new line in C?
By using ‘\n’ in printf statement
10. What is String?
String is colection of characters enclosed with in double quotes.
Ex :- “asdfg”, “apple”
11. How to write one string in two lines?
By using \
Ex :- “good mo\
Rning”