int red=3;
int blue=4;
void setup() {
  // put your setuputput code here, to run once:
pinMode(red,OUTPUT);
pinMode(blue,OUTPUT);
}

void loop(){ // put your main coide here, to run repeatedly:
digitalWrite(red,HIGH);
digitalWrite(blue, LOW);
delay(1000);
digitalWrite(red, LOW);
digitalWrite(blue, HIGH);
delay(1000);


}