void setup() {
  // put your setup code here, to run once:
pinMode(2, OUTPUT);
pinMode(3, OUTPUT);
pinMode(4, OUTPUT);

}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(2,1);
delay(5000);
digitalWrite(2,0);
digitalWrite(3,1);
delay(5000);
digitalWrite(3,0);
digitalWrite(4,1);
delay(5000);
digitalWrite(4,0);
}