int TIME = 1000;

void setup() 

{
 for (int x = 2; x <= 4; x++)
  {
   pinMode(x, OUTPUT);
  }
}

void loop() 

{ 
 for (int x = 2; x <= 4; x++)
  {
   digitalWrite(x, HIGH);
   delay(TIME);
   digitalWrite(x, LOW);
   delay(TIME);
  }
}


//---//