int button1 = 2;
int button2 = 3;
int button3 = 4;

int led[] = {5,6,7,8,9,10,11,12,13};

int count1 = 0;
int count2 = 0;
int count3 = 0;

int state1, state2, state3;
int lastState1 = 0;
int lastState2 = 0;
int lastState3 = 0;

void setup() {

  for(int i=0; i<9; i++){
    pinMode(led[i], OUTPUT);
  }

  pinMode(button1, INPUT);
  pinMode(button2, INPUT);
  pinMode(button3, INPUT);

  Serial.begin(9600);
}

void loop() {

  state1 = digitalRead(button1);
  state2 = digitalRead(button2);
  state3 = digitalRead(button3);

  // Push Button 1
  if(state1 == HIGH && lastState1 == LOW){
    count1++;

    if(count1 > 3){
      count1 = 0;
    }

    Serial.print("Button 1 ditekan : ");
    Serial.println(count1);

    updateLED();
    delay(200);
  }

  // Push Button 2
  if(state2 == HIGH && lastState2 == LOW){
    count2++;

    if(count2 > 3){
      count2 = 0;
    }

    Serial.print("Button 2 ditekan : ");
    Serial.println(count2);

    updateLED();
    delay(200);
  }

  // Push Button 3
  if(state3 == HIGH && lastState3 == LOW){
    count3++;

    if(count3 > 3){
      count3 = 0;
    }

    Serial.print("Button 3 ditekan : ");
    Serial.println(count3);

    updateLED();
    delay(200);
  }

  lastState1 = state1;
  lastState2 = state2;
  lastState3 = state3;
}

void updateLED(){

  // Matikan semua LED
  for(int i=0; i<9; i++){
    digitalWrite(led[i], LOW);
  }

  // LED untuk button 1
  for(int i=0; i<count1; i++){
    digitalWrite(led[i], HIGH);
  }

  // LED untuk button 2
  for(int i=3; i<3+count2; i++){
    digitalWrite(led[i], HIGH);
  }

  // LED untuk button 3
  for(int i=6; i<6+count3; i++){
    digitalWrite(led[i], HIGH);
  }
}