exercise 2

int greenLedPin = 10;
int yellowLedPin = 9;
void setup() {
 pinMode(greenLedPin, OUTPUT);
 pinMode(yellowLedPin, OUTPUT);
}
void loop() {
    for (int brightness=0; brightness <256; brightness++) {
    analogWrite(greenLedPin, brightness  );
    analogWrite(yellowLedPin, 256 - brightness );
 delay(10);
    }
   for (int brightness=256; brightness >0; brightness--) {
        analogWrite(greenLedPin, brightness );
        analogWrite(yellowLedPin, 256 - brightness );
 delay(10);
    }



}