const int red_led = 10;
const int yellow_led = 6;
const int green_led = 2;

void setup() {
  // put your setup code here, to run once:
pinMode(red_led, OUTPUT);
pinMode(yellow_led, OUTPUT);
pinMode(green_led, OUTPUT);


}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(10, HIGH);
digitalWrite(6, LOW);
digitalWrite(2, LOW);
delay(500);

digitalWrite(10, LOW);
digitalWrite(6, HIGH);
digitalWrite(2, LOW);
delay(200);

digitalWrite(10, LOW);
digitalWrite(6, LOW);
digitalWrite(2, HIGH);
delay(100);


}