/*Arrays*/
int t = 500;
int led[]={2, 3, 4, 5, 6, 7};
int jlhled = 6; //jumlah led
void setup() {
  for (int a = 0; a < jlhled; a++) {
    pinMode(led[a], OUTPUT);
  }
}
void loop() {
  for (int a = 0; a < jlhled; a++) {
    digitalWrite(led[a], HIGH);
    delay(t);
    digitalWrite(led[a], LOW);
  }
  for (int a = jlhled-1; a>=0; a--) {
    digitalWrite(led[a], HIGH);
    delay(t);
    digitalWrite(led[a], LOW);
  }
}