Semaphore with Arduino

//Green Pin 2
//Yellow pin 3
//Red pin 4
//////////// made by VINICIUS LOPES //////////////

void setup (){
pinMode(2, OUTPUT);// green
pinMode(3, OUTPUT);// yellow
pinMode(4, OUTPUT);// red
}
void loop (){

  
digitalWrite(4,HIGH);
delay(7000);
digitalWrite(4,LOW);
delay(100);

digitalWrite(3,HIGH);
delay(3000);
digitalWrite(3,LOW);
delay(100);

digitalWrite(2,HIGH);
delay(7000);
digitalWrite(2,LOW);
delay(100);

}