int A = 2;
int B = 3;
int LED = 13;

int mode = 0; 
// Jika akan menjalankan operasi yang lain rubah seperti ketentuan di bawah 
// 0 = AND
// 1 = OR
// 2 = NAND

void setup() {
  pinMode(A, INPUT_PULLUP);
  pinMode(B, INPUT_PULLUP);
  pinMode(LED, OUTPUT);
}

void loop() {
  int a = !digitalRead(A);
  int b = !digitalRead(B);

  if (mode == 0) {
    digitalWrite(LED, a && b); // AND
  } 
  else if (mode == 1) {
    digitalWrite(LED, a || b); // OR
  } 
  else if (mode == 2) {
    digitalWrite(LED, !(a && b)); // NAND
  }
}