const int led1 = 2; // pin LED 1
const int led2 = 3; // pin LED 2
const int led3 = 4; // pin LED 3
const int led4 = 5; // pin LED 4
const int tombolMode = 6; // pin tombol mode
int mode = 0; // mode saat ini

void setup() {
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
  pinMode(led4, OUTPUT);
  pinMode(tombolMode, INPUT);

  Serial.begin(9600);
}

void loop() {
  if (digitalRead(tombolMode) == HIGH){
    mode = mode + 1;
  }
  if (mode == 4) {
    mode = 0
  }
  switch (mode) {
    case 0:
      digitalWrite(led1, HIGH);
      digitalWrite(led2, LOW);
      digitalWrite(led3, LOW);
      digitalWrite(led4, LOW);
      break;
    case 1:
      digitalWrite(led1, LOW);
      digitalWrite(led2, HIGH);
      digitalWrite(led3, LOW);
      digitalWrite(led4, LOW);
      break;
    case 2:
      digitalWrite(led1, LOW);
      digitalWrite(led2, LOW);
      digitalWrite(led3, HIGH);
      digitalWrite(led4, LOW);
      break;
    case 3:
      digitalWrite(led1, LOW);
      digitalWrite(led2, LOW);
      digitalWrite(led3, LOW);
      digitalWrite(led4, HIGH);
      break;
    case 4:
      // kode Manual
      break;
  }
  Serial.println(mode);
}