void setup()
{
  pinMode((12, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode((9, OUTPUT);
  pinMode((8, OUTPUT);
}
void loop()
{
  digitalWrite(12, HIGH);
  digitalWrite(10, LOW);
  digitalWrite(9, LOW);
  digitalWrite(8, LOW;
  delay(1000);

  digitalWrite(12, LOW);
  digitalWrite(10, HIGH);
  digitalWrite(9, LOW);
  digitalWrite(8, LOW;
  delay(2000);

  digitalWrite(12, LOW);
  digitalWrite(10, LOW);
  digitalWrite(9, HIGH);
  digitalWrite(8, LOW;
  delay(1000);

  digitalWrite(12, LOW);
  digitalWrite(10, LOW);
  digitalWrite(9, LOW);
  digitalWrite(8, HIGH);
  delay(2000);

}