unsigned int Ketikan=0;

#define LED 2

void setup() {

pinMode(LED, OUTPUT);

  Serial.begin(115200);

  Serial.println("Aokowkwkwk ");
  Serial.println("Kalkulator ");
  Serial.println("By Jagoan Bot");
  Serial.println("---------- ");
}

void loop() {

  if(Serial.available())
  {
    Ketikan=Serial.read()-48;
  //Ketikan++;
    Serial.println(Ketikan);
  //Serial.write(Ketikan);
  }

  delay(10);
  digitalWrite(LED, HIGH);
  delay(500);
  digitalWrite(LED, LOW);
  delay(500);
}