Variables and data types

Basic data types

Data type	Description	Examples
INTEGER	A whole number	5, -267, 153489
REAL	A number with decimal point	3.142, 56.0, -0.75
CHAR	A single character enclosed in single quotes	'K', '#', '6'
STRING	Zero or more characters enclosed in double quotes	"Yes", "Hi, John"
BOOLEAN	The logical values TRUE and FALSE	TRUE, FALSE

Variable declarations

// DECLARE {identifier} : {data type}

DECLARE Counter : INTEGER
DECLARE TotalToPay : REAL
DECLARE GameOver : BOOLEAN

Assignments

// {identifier} <- {value}

// Should declare variable first and then assign it
DECLARE Counter : INTEGER

Counter <- 0
Counter <- Counter + 1
OUTPUT Counter

Exercises

Exercise

Which of the following are valid variable names?

1. myBestScore

2. Name

3. 1stClass

4. cost_of_meal

5. Print84

6. A-1

7. _1234

Answer

2, 5

Exercise

For each of thee following variables, state whether they need to be of STRING, INTEGER or REAL type.

1. Price

2. NumberOfSiblings

3. Name

Answer

1. REAL

2. INTEGER

3. STRING

Exercise

Predict what is printed when runs these statements.

X <- 5
Y <- 10
X <- Y
Y <- 5

OUTPUT X
OUTPUT Y