void setup() {
  pinMode(13, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(7, INPUT_PULLUP);
}
void loop() {
  digitalWrite(13, HIGH);
  delay(2000);
  digitalWrite(13, LOW);
  delay(2000);

  bool sw = digitalRead(7);
  if (sw == 0) {
    digitalWrite(12, HIGH);
  }
  else {
    digitalWrite(12, LOW);
  }
}