55 lines
1.5 KiB
Markdown
55 lines
1.5 KiB
Markdown
# counter quiz answers
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Learn how to create a counter with the BBC micro:bit button.
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This is the answer key for the [counter quiz](/lessons/counter/quiz).
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## 1. What is a variable?
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Answers may vary but a variable is a place where you can store and retrieve data
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## 2. Draw the stored value for the variable called count
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```blocks
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let count = 0
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```
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We create a **variable**, `count` to keep track of the current count. The number 0 is stored into memory of the variable.
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<br/>
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## 3. Draw which LEDs are ON after running this code and pressing button "A" once. Explain you chose to draw that number
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```blocks
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let count = 0
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input.onButtonPressed(Button.A, () => {
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count = count + 1
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basic.showNumber(count)
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})
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```
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We are only pressing on button pressed once. So the number to display on the micro:bit is also one.
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<br/>
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## 4. Draw which LEDs are ON after running this code and pressing button "A" three times. Explain you chose to draw that number
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```blocks
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let count = 0
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input.onButtonPressed(Button.A, () => {
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count = + 1
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basic.showNumber(count)
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})
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```
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We included the code ``on button pressed("A")`` that runs each time the user presses A. The code increments `count` by `1`. We increase `count` by 1 whenever the user presses the button. So the third time the A button is pressed on the BBC micro:bit, the number 3 is displayed
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<br/>
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