void setup() {
pinMode(33, OUTPUT);
pinMode(20, OUTPUT);
pinMode(18, OUTPUT);
}
void loop()
{
digitalWrite(33, HIGH);
delay(50);
digitalWrite(20, HIGH);
delay(50);
digitalWrite(18, HIGH);
delay(50);
digitalWrite(33, LOW);
delay(50);
digitalWrite(20, LOW);
delay(50);
digitalWrite(18, LOW);
delay(50);
}