int s0=11;
int s1=10; 
int s2=9;
int s3=6;




void setup() {
  pinMode(s0,OUTPUT);
  pinMode(s1,OUTPUT);
  pinMode(s2,OUTPUT);
  pinMode(s3,OUTPUT);
  pinMode(3, OUTPUT);

}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(3, HIGH);
  digitalWrite(s0, HIGH);
  digitalWrite(s1, HIGH);
  digitalWrite(s2, LOW);
  digitalWrite(s3, LOW);
  delay(3000);

digitalWrite(s0, LOW);
  digitalWrite(s1, LOW);
  digitalWrite(s2, LOW);
  digitalWrite(s3, LOW);
  delay(3000);

  digitalWrite(s0, LOW);
  digitalWrite(s1, LOW);
  digitalWrite(s2, HIGH);
  digitalWrite(s3, HIGH);
  delay(3000);
}