void setup(){
pinMode(8,OUTPUT); //sets the number 0 digital pin of the Arduino in output mode
pinMode(9,OUTPUT); //sets the number 1 digital pin of the Arduino in output mode
pinMode(12,OUTPUT);
}
 
void loop(){
delay(2000);

digitalWrite(8,HIGH); //red LED lights up
//goto pp;
digitalWrite(9,LOW); //green LED goes out

delay(1500);
digitalWrite(8,LOW); //red LED goes out
digitalWrite(9,HIGH); //green LED lights up
delay(1000);
//pp:;

digitalWrite(12,HIGH); //red LED lights up
delay(1500);
digitalWrite(12,LOW); //green LED goes out

delay(500);
}