void setup()
{
  pinMode(10,OUTPUT);
  pinMode(9,OUTPUT);
  pinMode(8,OUTPUT);
}
void loop()
{
   digitalWrite(10,LOW);
   digitalWrite(9,LOW);
   digitalWrite(8,HIGH);
   delay(1000);
   digitalWrite(10,LOW);
   digitalWrite(9,HIGH);
   digitalWrite(8,LOW);
   delay(1000);
   digitalWrite(10,HIGH);
   digitalWrite(9,LOW);
   digitalWrite(8,LOW);
   delay(1000);
}