const int LEDANZAHL = 7;
const int LEDSON    = 1;
const int led_pin[LEDANZAHL] = {7, 8, 9, 10, 11, 12, 13};
const int Zeit = 200;

void setup() {
  for (int i = 0; i < LEDANZAHL; i++) {
    pinMode(led_pin[i], OUTPUT);
  }
}

void ledSwitch (int von, int bis) {
  for(int i = 0; i < LEDANZAHL; i++ ) {
    digitalWrite(led_pin[i], LOW);
  }
  for(int i = von; i <= bis; i++ ) {
    digitalWrite(led_pin[i], HIGH);
  }
}

void kit() {
  for (int i = 0; i <= LEDANZAHL - LEDSON ; i++) {
    ledSwitch(i,i+LEDSON-1);
    delay(Zeit);
  }
  for(int i = LEDANZAHL - 1 - LEDSON; i >= 1; i-- ) {
    ledSwitch(i,i+LEDSON-1);
    delay(Zeit);
  }
}

void blinker () {
  for(int i=0; i<LEDANZAHL; i++) {
    ledSwitch(0,i);
    delay(Zeit);
  }
}

void loop () {
  blinker();
}