int jeda = 200;
int pinLED [] = {51, 50, 49, 48, 47, 46, 45, 44};
int jmlLED = 8;

void setup() {
  for (int ulang = 0; ulang < jmlLED; ulang++) {
    pinMode(pinLED[ulang], OUTPUT);
  }

}

void loop() {
  for(int ulang = 0; ulang < jmlLED; ulang++) {
    digitalWrite(pinLED[ulang], 1);
    delay(jeda);
    digitalWrite(pinLED[ulang], 0);
  }

  for(int ulang = jmlLED - 1; ulang >= 0; ulang--) {
    digitalWrite(pinLED[ulang], 1);
    delay(jeda);
    digitalWrite(pinLED[ulang], 0);
  }

}