73 lines
1.4 KiB
Markdown
73 lines
1.4 KiB
Markdown
# strobe light challenges
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Coding challenges for strobe light.
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## Before we get started
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Complete the following [guided tutorial](/lessons/strobe-light/activity), your code should look like this:
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```blocks
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for (let i = 0; i < 5; i++) {
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for (let j = 0; j < 5; j++) {
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led.plot(i, j)
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basic.pause(200)
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}
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}
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```
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### Challenge 1
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### @video td/videos/strobe-light-1
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Make the LEDs light up faster by changing the **pause** from 200 to 100 milliseconds:
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```blocks
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for (let i = 0; i < 5; i++) {
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for (let j = 0; j < 5; j++) {
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led.plot(i, j)
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basic.pause(100)
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}
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}
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```
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* Run the code to see if it works as expected.
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### Challenge 2
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### @video td/videos/strobe-light-2
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Make the board light up by rows instead of by columns by swapping the `i` and `j` variables in `plot(i, j)`.
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```blocks
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for (let i = 0; i < 5; i++) {
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for (let j = 0; j < 5; j++) {
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led.plot(j, i)
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basic.pause(100)
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}
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}
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```
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* Run the code to see if it works as expected.
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### Challenge 3
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### @video td/videos/strobe-light-ultimate
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Now that all the LEDs are lit up, let's make them turn off by reversing the strobe light pattern! You can use `unplot` to turn off a single LED.
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```blocks
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for (let i = 0; i < 5; i++) {
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for (let j = 0; j < 5; j++) {
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led.plot(j, i)
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basic.pause(100)
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}
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}
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for (let k = 0; k < 5; k++) {
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for (let l = 0; l < 5; l++) {
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led.unplot(4 - l, 4 - k)
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basic.pause(100)
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}
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}
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``` |