void setup() 
{
pinMode(2,OUTPUT); // put your setup code here, to run once:
pinMode(3,OUTPUT);
}
void loop()
{ 
digitalWrite(2,HIGH); // put your main code here, to run repeatedly:
digitalWrite(3,LOW);
delay(1000);
digitalWrite(2,LOW);
digitalWrite(3,HIGH);
delay(1000);
digitalWrite(2,HIGH);
digitalWrite(3,HIGH);
delay(1000);
digitalWrite(2,LOW);
digitalWrite(3,LOW);
delay(1000);
}