int ledMerah = 8;
int ledKuning = 9;
int ledHijau = 10;


void setup() {
Serial.begin(9600);
pinMode(ledMerah, OUTPUT);
pinMode(ledKuning, OUTPUT);
pinMode(ledHijau, OUTPUT);
}

void loop() {
digitalWrite(ledMerah, HIGH);
delay(2000);
digitalWrite(ledMerah, LOW);

digitalWrite(ledKuning, HIGH);
delay(2000);
digitalWrite(ledKuning, LOW);

digitalWrite(ledHijau, HIGH);
delay(2000);
digitalWrite(ledHijau, LOW);
}