int red_led = 11;
int green_led = 10;
int blue_led = 9;
int yellow_led = 8;


void setup() {
  // set up all of my led pins
  pinMode(red_led, OUTPUT);
  pinMode(green_led, OUTPUT);
  pinMode(blue_led, OUTPUT);
  pinMode(yellow_led, OUTPUT);

  // turns all of my leds for 1 second
  digitalWrite(red_led, HIGH);
  digitalWrite(green_led, HIGH);
  digitalWrite(blue_led, HIGH);
  digitalWrite(yellow_led, HIGH);
  delay(1000);

  // turns all leds off for 1 second
  digitalWrite(red_led, LOW);
  digitalWrite(green_led, LOW);
  digitalWrite(blue_led, LOW);
  digitalWrite(yellow_led, LOW);
  delay(1000);
}

void loop() {
  // turns on only red for 1 second
  digitalWrite(red_led, HIGH);
  digitalWrite(green_led, LOW);
  digitalWrite(blue_led, LOW);
  digitalWrite(yellow_led, LOW);
  delay(1000);

  // turns on only green for 1 second
  digitalWrite(red_led, LOW);
  digitalWrite(green_led, HIGH);
  digitalWrite(blue_led, LOW);
  digitalWrite(yellow_led, LOW);
  delay(1000);

  // turns on only blue for 1 second
  digitalWrite(red_led, LOW);
  digitalWrite(green_led, LOW);
  digitalWrite(blue_led, HIGH);
  digitalWrite(yellow_led, LOW);
  delay(1000);

  //turns on only yellow for 1 second 
  digitalWrite(red_led, LOW);
  digitalWrite(green_led, LOW);
  digitalWrite(blue_led, LOW);
  digitalWrite(yellow_led, HIGH);
  delay(1000);

  analogWrite(red_led, 0);
  analogWrite(green_led, 0);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 15);
  analogWrite(green_led, 0);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 95);
  analogWrite(green_led, 0);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 175);
  analogWrite(green_led, 0);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 255);
  analogWrite(green_led, 0);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 175);
  analogWrite(green_led, 0);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 95);
  analogWrite(green_led, 0);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 15);
  analogWrite(green_led, 0);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 0);
  analogWrite(green_led, 15);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 0);
  analogWrite(green_led, 95);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 0);
  analogWrite(green_led, 175);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 0);
  analogWrite(green_led, 255);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 0);
  analogWrite(green_led, 175);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 0);
  analogWrite(green_led, 95);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 0);
  analogWrite(green_led, 15);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);

  analogWrite(red_led, 0);
  analogWrite(green_led, 0);
  analogWrite(blue_led, 0);
  analogWrite(yellow_led, 0);
  delay(500);
}