void setup(){
  pinMode(A1, INPUT);
  pinMode(5, OUTPUT);
}

void loop(){
  if (!analogRead(A1)) {
    for (int i = 0; i <= 255; i = i + (3)) {
      if (analogRead(A1)) {
        analogWrite(5, i);
        break;

      }
      analogWrite(5, i);
      delay(10);
    }
    for (int i = 255; i >= 0; i = i + (-3)) {
      if (analogRead(A1)) {
        analogWrite(5, i);
        break;

      }
      analogWrite(5, i);
      delay(10);
      if (i == 0) {
        delay(10);

      }
    }

  }

}