int led [5] = {0, 5, 4, 3, 2};       //Pin der LED
int buttonPin = 8;   //Pin zum auslesen des Knopfs
int i = 0;
int j = 0;
int binary [4] = {0, 0, 0, 0};

void Umwandler(int dezimal, int binary[]) {
  int index = 0;
  while (dezimal > 0) {
    binary[index] = dezimal % 2;
    dezimal = dezimal / 2;
    index++;
  }
}

void setup() {
  for (int j = 0; j < 4; ++j) {
    pinMode(led[j + 1], OUTPUT);
  }
  pinMode(buttonPin, INPUT);
}

void loop() {
  if (digitalRead(buttonPin) == HIGH) {
    i++;
    delay(50);
    while (digitalRead(buttonPin) == HIGH) {
      delay(150);
    }
  }
  Umwandler(i, binary);
  for (int j = 0; j < 4; ++j) {
    digitalWrite(led[j + 1], binary[j] ? HIGH : LOW);
  }
  if (i > 15) {
    i = 1;
  }
}