msev.cpp

#define BUTTON_PIN_A0 A0
#define BUTTON_PIN_A1 A1
int previousStateA0;
int previousStateA1;

void setup() {
 
  Serial.begin(9600);
  previousState = 0;
}
 
void loop() {
 updateButton(BUTTON_PIN_A0, previousStateA0);
 updateButton(BUTTON_PIN_A1, previousStateA1);
}

void updateButton(int pin, int &holder){
  int analogValue = analogRead(pin);
 
  int actualState;
  if(analogValue < 100) actualState = 1;
  else if(analogValue < 900) actualState = 3;
  else actualState = 2;
 
  if(*holder != actualState) {
    *holder = actualState;
    Serial.print("Button state: ");
    Serial.println(actualState);
  }
}