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void setup() {
  pinMode(LED_BUILTIN, OUTPUT);
  pinMode(11, OUTPUT);
}

void loop() {
  int a;
  a = analogRead(A0);
  if (a > 3) {
    digitalWrite(LED_BUILTIN, HIGH);
    digitalWrite(11, HIGH);
    delay(50);
  } else {
    digitalWrite(LED_BUILTIN, LOW);
    digitalWrite(11, LOW);
  }  
}