int greenledpin = 10;
int redledpin = 11;
int yellowledpin = 12;

void setup() {
  // put your setup code here, to run once:
pinMode(redledpin, OUTPUT);
pinMode(greenledpin, OUTPUT);
pinMode(yellowledpin, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(greenledpin, HIGH);
digitalWrite(redledpin, HIGH);
digitalWrite(yellowledpin, HIGH);
delay(500);

digitalWrite(greenledpin, LOW);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, HIGH);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, LOW);
digitalWrite(redledpin, HIGH);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, HIGH);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);


digitalWrite(greenledpin, LOW);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, HIGH);
delay(500);

digitalWrite(greenledpin, HIGH);
digitalWrite(redledpin, HIGH);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, LOW);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, HIGH);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, LOW);
digitalWrite(redledpin, HIGH);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, HIGH);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, HIGH);
delay(500);

digitalWrite(greenledpin, LOW);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, HIGH);
digitalWrite(redledpin, HIGH);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, LOW);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);


digitalWrite(greenledpin, HIGH);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, LOW);
digitalWrite(redledpin, HIGH);
digitalWrite(yellowledpin, HIGH);
delay(500);

digitalWrite(greenledpin, HIGH);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, LOW);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, HIGH);
digitalWrite(redledpin, HIGH);
digitalWrite(yellowledpin, LOW);
delay(500);

digitalWrite(greenledpin, LOW);
digitalWrite(redledpin, LOW);
digitalWrite(yellowledpin, LOW);
delay(500);
}