Variables in C

Question 1

What is a variable?

Answer 1

References to memory locations

Allow us to use names rather than memory addresses to access and manipulate data

Question 2

Types of variable

Answer 2

char
int
double
float

Question 3

Variable type qualifiers

Answer 3

signed - can hold positive and negative numbers
unsigned - can only hold positive numbers
short - –32768 to 32,767
long - –2,147,483,648 to 2,147,483,647

Question 4

sizeof() does what?

Answer 4

used to check the size of a variable in bytes

Question 5

Where must variables be declared?

Answer 5

They must be declared in the variable declaration section before use AT THE START OF THE FUNCTION AND BEFORE ANY STATEMENTS

Question 6

What is the value of a variable if it has been declared but not been assigned a value?

Answer 6

Most compilers set the value to 0 and this zero is constant

Question 7

What is a constant?

Answer 7

A constant is a variable whose value cannot be modified and is essentially read-only