# @extends
## #examples
## Example: Count to 4
This program will show the numbers 0, 1, 2, 3, and 4 one after another on the LED screen.
```blocks
input.onButtonEvent(Button.A, ButtonEvent.Down, () => {
for(let i = 0; i < 5; ++i) {
basic.showNumber(i)
}
})
```