Programming Variables Quiz

12 Questions

What is the purpose of declaring a variable type?

To allocate memory for the variable

Which of the following is not a valid variable name in most programming languages?

123variable

In C programming, which data type is used to store whole numbers?

int

What will be the value of x after the following expression in C: x = 5 + 3 * 2;

What is an expression in programming?

A combination of operators and operands that evaluates to a value

In an expression, what is the role of parentheses?

To group operations and change precedence

What does the % operator do in programming?

It returns the remainder of a division operation

Which statement is used to repeat code until a condition is met?

while

In programming, what does the 'else' statement do in an if-else construct?

To execute a block of code if the condition is false

What is the output of the expression (3 * 7) in a conditional statement?

$21$

In a conditional statement, what does the '==' symbol represent?

'Equal to'

If none of the conditions in an if-else if-else ladder are met, what happens?

The program skips the conditional statements and proceeds with the next instruction.

Study Notes

Variables

A variable is a storage location with an associated symbolic name.
Examples of valid variable names: myVariable, _variable, variable1.
Invalid variable name: 123variable (starts with a number).
Declaring a variable type:
- Specifies the type of data the variable can hold.
- Allocates memory for the variable.
- Does not specify the variable's value or name.

Data Types

In C programming, int is the data type used to store whole numbers.
Other data types: float, char, double.

Variable Scope

Global variables can be accessed from any part of the program.
Local variables are declared within a function and can only be accessed within that function.

Expressions

An expression is a combination of operators and operands that evaluates to a value.
Examples of expressions: x = 5 + 3 * 2;, 10 % 3.
In an expression, parentheses define the order of operations.

Operators

Arithmetic operators: +, ++, *, /.
% is the modulus operator, which finds the remainder of a division operation.
!= is the "not equal to" operator in a conditional statement.

Conditionals

The if statement is used to execute code based on a condition.
The else statement executes a block of code if the condition is false.
In an if-else if-else ladder, if none of the conditions are true, the code in the else block is executed.