Showing a counter in a flowchart

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Quick Questions

Shade in the A or B circle for each question.

1. Which shape holds the step 'set count to 0' in a flowchart?

A A decision diamond

B A step box (rectangle)

2. Where should 'set count to 0' go in a flowchart with a counter?

A Inside the loop

B Before the loop starts

3. Which step adds one to the counter?

A count ← count + 1

B count ← 1

4. What shape is used for the question 'count = 5?'

A A decision diamond

B A step box

5. The diamond 'count = 5?' says No. What happens next?

A The arrow goes back and the loop runs again

B The flowchart ends

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
1count ← 0		AA step box before the loop that sets the counter to 0 so counting starts from zero
2count ← count + 1		BThe counter never goes up because there is no count ← count + 1 step inside the loop, so count = 5? is never Yes.
3The decision diamond asks if the counter has reached the target. Yes leaves the loop and No goes round again.		CA step box inside the loop that adds 1 to the counter each time round
4The counter must start at zero in a step box before the loop begins		Dcount ← 0
5Loop step box: count ← 0 (inside the loop, before the diamond count = 5?)		Ecount = 5? Yes or No
6Loop: Print Hello, then diamond count = 5? and no step box that adds 1 to count		Fcount is set back to 0 every time round the loop, so it never reaches 5 and the loop never ends. Set it to 0 once before the loop.

Definitions

count ← count + 1

Fill in the Blanks

Complete each line of code by filling in the missing parts.

Step box: count ← _

Loop step box: count ← count _ 1

Loop step box: count ← count + _

Diamond: _____ = 5?

Diamond: count = 5? ___ -> leave the loop No -> go round again

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A START

B Step box: count ← 5

C Step box: count ← count + 1

D Diamond: count = 5?

E Yes: END. No: back to line 3

Question 2

A START

B count ← 0

C count ← count - 1

D Diamond: count = 5?

E No: go back to line 3

F Yes: END

Question 3

A START

B count ← 0

C count ← count + 1

D Box: count = 5?

E Yes: END

Question 4

A START

B Step box: count ← 0

C Diamond: count ← count + 1

D Diamond: count = 5?

Question 5

A START

B Set count to 1

C Add 1 to count

D Is count = 5?

E No: go back to Add 1

Answer Key

Showing a counter in a flowchart

Section A: Quick Questions

B — A step box (rectangle)

B — Before the loop starts

A — count ← count + 1

A — A decision diamond

A — The arrow goes back and the loop runs again

Section B: Match the Pairs

count ← 0 → A step box before the loop that sets the counter to 0 so counting starts from zero

count ← count + 1 → A step box inside the loop that adds 1 to the counter each time round

The decision diamond asks if the counter has reached the target. Yes leaves the loop and No goes round again. → count = 5? Yes or No

The counter must start at zero in a step box before the loop begins → count ← 0

Loop step box: count ← 0 (inside the loop, before the diamond count = 5?) → count is set back to 0 every time round the loop, so it never reaches 5 and the loop never ends. Set it to 0 once before the loop.

Loop: Print Hello, then diamond count = 5? and no step box that adds 1 to count → The counter never goes up because there is no count ← count + 1 step inside the loop, so count = 5? is never Yes.

Section C: Definitions

count ← count + 1 — A flowchart counter: set count to 0 in a step box, add 1 inside the loop, then ask count = 5? in a diamond. Yes leaves the loop, No goes round again.

Section D: Fill in the Blanks

Step box: count ← 0

Loop step box: count ← count + 1

Diamond: count = 5?

Diamond: count = 5?
Yes -> leave the loop
No -> go round again

Section E: Spot the Error

B — The counter must start at 0 before the loop. If it starts at 5, the test count = 5? is already true. The line should be: Step box: count ← 0.

C — The counter goes up by 1 each time round the loop. Taking 1 away would take count further from 5. It should be count ← count + 1.

D — A question with a Yes or No answer goes in a decision diamond, not a step box. It should be Diamond: count = 5?.

C — Adding 1 is an action, so it belongs in a step box. A diamond is only for Yes/No questions. It should be Step box: count ← count + 1.

B — The count should start at 0 so that it counts all 5 times round the loop. Starting at 1 would stop after only 4 loops. It should be Set count to 0.