int led1 = 13;
int led2 = 12;
int button = 3;

void setup() {
  // put your setup code here, to run once:
pinMode(led1, OUTPUT);
pinMode(led2, OUTPUT);
pinMode(button, INPUT_PULLUP);
}

void loop() {
  // put your main code here, to run repeatedly:
bool buttonState = digitalRead(button);



  digitalWrite(led1, HIGH);
  delay(500);
digitalWrite(led1, LOW);
delay(500);

  digitalWrite(led2, HIGH);
  delay(500);
  digitalWrite(led2, LOW);
  delay(500);
}