int SW[] = {25,26,27};
int count = 0;
int last1 = 0;
int last2 = 0;

void setup(){
  Serial.begin(9600);

  for(int i = 0 ; i <= 2 ; i++){
    pinMode(SW[i], INPUT);
    delay(50);
  }
}

void loop(){
  if(digitalRead(SW[0]) == 1 && last1 == 0){
    count++;
  }
  last1 = digitalRead(SW[0]);

  if(digitalRead(SW[1]) == 1 && last2 == 0){
    count--;
  }
  last2 = digitalRead(SW[1]);

  if(digitalRead(SW[2]) == 1){
    count = 0;
  }

  Serial.println(count);
}