int redPin = 9;   // choose the pin for the red LED
int greenPin = 10; // choose the pin for the green LED
int bluePin = 11;  // choose the pin for the blue LED

void setup() {
  pinMode(redPin, OUTPUT);   // initialize the red LED pin as an output
  pinMode(greenPin, OUTPUT); // initialize the green LED pin as an output
  pinMode(bluePin, OUTPUT);  // initialize the blue LED pin as an output
}

void loop() {
  // set the LED color to red
  digitalWrite(redPin, HIGH);
  digitalWrite(greenPin, LOW);
  digitalWrite(bluePin, LOW);
  delay(1000);

  // set the LED color to green
  digitalWrite(redPin, LOW);
  digitalWrite(greenPin, HIGH);
  digitalWrite(bluePin, LOW);
  delay(1000);

  // set the LED color to blue
  digitalWrite(redPin, LOW);
  digitalWrite(greenPin, LOW);
  digitalWrite(bluePin, HIGH);
  delay(1000);
}