Unit 5 : Algorithm - Repetition Structure

Question 1

What is repetition structure?

Answer 1

1. Specifies a block of one or more statements that are repeatedly executed until a condition is satisfied

Question 2

What are the types of repetition structure? ( 2 )

Answer 2

1. Counter Based
2. Sentinel Based

Question 3

List out the 2 important parts of a loop

Answer 3

1. An expression that is tested for a true / false
2. A statement or block that is repeated if the expression is true

Question 4

What is a counter based repetition structure? ( 1 )

Answer 4

1. It can be used to control number of execution of the loop

Question 5

What do we need to do when setting up a counter? ( 2 )

Answer 5

1. Initialized before entering loop ( i )
2. It will increase or decrease each time a loop repeats

Question 6

What is sentinel repetition structure mostly based on ?

Answer 6

1. User input

• User input determintes loop repetition
  Their input is prompt before loop so that then the input is used to control number of repetitions

Question 7

What are the pseudocode for counter based pseudocode?

Answer 7

1. LOOP counter FROM InitVal TO EndVal STEP increment_value
   statement
   NEXT counter
   ENDLOOP

Question 8

What is the pseudocode for sentinel based repetition structure ?

Answer 8

DOWHILE (condition is true for value)
statement_block
Prompt user for value
Read value
ENDDO

Question 9

What shapes can flowchart represents repetition structure?

Answer 9

1. Hexagon

Question 10

What are the value that the hexagon repetition structure required in flowchart? ( 4 )

Answer 10

1. Variable Name
2. Initial Value
3. End Value
4. Increment / Decrement