int led1 = 9;
int led2 = 8;
int led3 = 7;
int led4 = 6;

// the setup routine runs once when you press reset:
void setup() {                
  // initialize the digital pin as an output.
  pinMode(led1, OUTPUT);     
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);     
  pinMode(led4, OUTPUT);
}


// the loop routine runs over and over again forever:
void loop() {
  digitalWrite(led1, HIGH);   
  delay(100);               
  digitalWrite(led1, LOW);    
  delay(20);               
  digitalWrite(led1, HIGH);   
  delay(100);               
  digitalWrite(led1, LOW);
  delay(0);    

  digitalWrite(led3, HIGH);   
  delay(250);               
  digitalWrite(led3, LOW);    
  delay(0);               

  digitalWrite(led2, HIGH);   
  delay(100);               
  digitalWrite(led2, LOW);    
  delay(20);               
  digitalWrite(led2, HIGH);   
  delay(100);               
  digitalWrite(led2, LOW);    
  delay(0);

  digitalWrite(led4, HIGH);   
  delay(250);               
  digitalWrite(led4, LOW);    
  delay(0);               

}