void setup() {
  pinMode(0,OUTPUT);
  pinMode(1,OUTPUT);
  pinMode(2,OUTPUT);
  pinMode(3,OUTPUT);
  pinMode(4,OUTPUT);
  pinMode(5,OUTPUT);
  // put your setup code here, to run once:

}

void loop() {
  for(int i=0; i<6; i++)
  {
    digitalWrite(i,HIGH);
    delay(200);
  }
  for(int i=6; i>=0; i--)
  {
    digitalWrite(i,LOW);
    delay(200);
  }
  // put your main code here, to run repeatedly:

}