int led1 = 8;
int led2 = 9;
void setup() {
  // put your setup code here, to run once:
pinMode(led1, OUTPUT);
pinMode(led2, OUTPUT);
}



void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(led1, HIGH);
digitalWrite(led2, LOW);
delay(1000);
digitalWrite(led1, LOW);
digitalWrite(led2, HIGH);
delay(1000);
}