Unit 3 : Algorithm Selection

Question 1

What does the selection control structure represent? （ 2 ）

Answer 1

1. Represents the decision making capabilities of computer
2. Used to illustrate a choice between two or more actions depending on whether the condition is true or false

Question 2

What is a condition? ( 2 )

Answer 2

1. Comparison between 2 items
2. Return True or False as answer

Question 3

List out all the relational operators and the meaning ( 6 )

Answer 3

1. < Less than
2. > Greater than
3. == Equal to
4. <= Less than or Equal to
5. > = Greater than or Equal to
6. != / <> - Not equal to

Question 4

What are logical operators?

Answer 4

1. Used to create relational expressions from other relational expressions

Question 5

List out all the logical operators ( 3 )

Answer 5

1. && - and, returns true if both expressions are true
2. || - or, return true if either expression is true
3. ! - not, returns true if none of the expression is true

Question 6

What is the peudocode of selection control structure?

Answer 6

IF ( condition ) THEN
//statement1
ELSE
//statement2
ENDIF

Question 7

What is the noun of this meaning? “A choice is made between two alternative paths, depending on the result of a
condition being true or false”

Answer 7

1. Selection Control Structure

Question 8

List out all the selection control structure ( 4 )

Answer 8

1. Simple Selection ( Simple IF statement )
2. Simple Selection with null false branch ( null ELSE statement )
3. Combined Selection (Combined IF statement with using AND , OR , NOT )
4. Nested Selection ( Nested IF statement , means if inside another if )

Question 9

What is the keyword for selection control structure? ( 5 )

Answer 9

1. IF
2. THEN
3. ELSE
4. ELSEIF
5. ENDIF