void setup() 
{
  pinMode(3,OUTPUT);
  pinMode(5,OUTPUT);
  pinMode(4,OUTPUT);
  pinMode(19,OUTPUT);
  pinMode(18,OUTPUT);
  pinMode(20,OUTPUT);

}

void loop()
{
  digitalWrite(3, LOW); 
  digitalWrite(4, LOW);
  digitalWrite(5, HIGH); 
  digitalWrite(19, LOW);
  digitalWrite(18, HIGH);
  digitalWrite(20, LOW);
  delay(1000);
  digitalWrite(3, LOW); 
  digitalWrite(4, HIGH);
  digitalWrite(5, LOW); 
  digitalWrite(19, HIGH);
  digitalWrite(18, LOW);
  digitalWrite(20, LOW);
  delay(1000);
  digitalWrite(3, HIGH); 
  digitalWrite(4, LOW);
  digitalWrite(5, LOW); 
  digitalWrite(19, LOW);
  digitalWrite(18, LOW);
  digitalWrite(20, HIGH);
  delay(1000);
  digitalWrite(3, LOW); 
  digitalWrite(4, HIGH);
  digitalWrite(5, LOW); 
  digitalWrite(19, HIGH);
  digitalWrite(18, LOW);
  digitalWrite(20, LOW);
  delay(1000);

}