void setup() {
  //
  pinMode(4, OUTPUT);
  pinMode(2, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(16, OUTPUT);
  pinMode(17, OUTPUT);
  pinMode(0, OUTPUT);
  pinMode(18, OUTPUT);
}

void loop() {
  //
   digitalWrite( 4, HIGH);
  delay(1000); // Wait for 1000 millisecond(s)
  digitalWrite( 4, LOW);

  delay(1000); // Wait for 1000 millisecond(s)
   digitalWrite( 2, HIGH);
  delay(1000); // Wait for 1000 millisecond(s)
  digitalWrite( 2, LOW);

  delay(1000); // Wait for 1000 millisecond(s)
   digitalWrite( 6, HIGH);
  delay(1000); // Wait for 1000 millisecond(s)
  digitalWrite( 6, LOW);
  delay(1000); // Wait for 1000 millisecond(s)

   digitalWrite( 16, HIGH);
  delay(1000); // Wait for 1000 millisecond(s)
  digitalWrite( 16, LOW);
  delay(1000); // Wait for 1000 millisecond(s)

   digitalWrite( 17, HIGH);
  delay(1000); // Wait for 1000 millisecond(s)
  digitalWrite( 17, LOW);
  delay(1000); // Wait for 1000 millisecond(s)

   digitalWrite( 0, HIGH);
  delay(1000); // Wait for 1000 millisecond(s)
  digitalWrite( 0, LOW);
  delay(1000); // Wait for 1000 millisecond(s)

   digitalWrite( 18, HIGH);
  delay(1000); // Wait for 1000 millisecond(s)
  digitalWrite( 18, LOW);
  delay(1000); // Wait for 1000 millisecond(s)
}