void setup() {
  Serial.begin(115200);

  for (int x = 7; x >= 2; x--) {
    pinMode(x, OUTPUT);
  }
}
///////////////////////////// end setup
void loop() {
  int xx;
  //hled();
  //lled();
  //nled(3);
  xx = sum(7,2);
  Serial.println(xx);
}
///////////////////////////// end loop
void hled() {

  for (int y = 7; y >= 2; y--) {
    digitalWrite(y, HIGH);
    delay(200);
  }
}

void lled()  {
  for (int y = 7; y >= 2; y--) {
    digitalWrite(y, LOW);
    delay(200);
  }
}

void nled(int n) {

  int led = 8;
  int num;
  num = led - n;
  for (int y = 7; y >= num; y--) {
    digitalWrite(y, HIGH);
  }
  delay(200);
}

int sum(int x, int y) {
  int res = 0;
  res = x+y;
  return res;
}