/* Note: Since we can use potantiometer as a sensor which connected
  to the power supply, we do not need the resistor.
  but if we use a temperature sensor, we do need a resistor.
  if we go to the docs, top right side of this page, 
  we can see many references. then we go to potentiometer, and in Simulator examples,
  we click on plot. the code below and circuit will be shown:
*/
void setup() {
  Serial.begin(115200);
  // ?? what is Serial.begin(115200);
  pinMode(A0, INPUT);
}

void loop() {
  int value = analogRead(A0);
  Serial.println(value);
  delay(100);
}