byte cuenta = 0;
unsigned long intervalo = 500, ValorAnterior = 0;

byte Led[] = {23, 22, 21, 19, 18, 5, 17, 16, 4, 2, 15};
byte bar[] = {16, 4, 2, 15};
byte Seg[] = {0x7E, 0x30, 0x6D, 0x79, 0x33, 0x5B, 0x5F, 0x70, 0x7F, 0x73};
int DIG[] = {0, 0, 0, 0};

void setup() {
  for (byte i = 0; i < sizeof(Led) / sizeof(Led[0]); i++)
    pinMode(Led[i], OUTPUT);
}

void loop() {
  if (millis() - ValorAnterior >= intervalo) {
    ValorAnterior += intervalo;
    DIG[3] = cuenta / 1000;
    DIG[2] = (cuenta % 1000) / 100;
    DIG[1] = (cuenta % 100) / 10;
    DIG[0] = cuenta % 10;
    cuenta = (cuenta + 1) % 10000;
  }

  for (byte i = 0; i < 4; i++) {
    barrido(i);
    display(Seg[DIG[i]]);
    delay(5);
  }
}

void display(byte N) {
  byte j, m = 7;
  for (byte i = 0; i <= 6; i++) {
    j = (2, m);  // Corrección del pow()
    digitalWrite(Led[i], (N & j) ? LOW : HIGH);
    m--;
  }
}

void barr(byte a, byte b, byte c, byte d) {
  digitalWrite(bar[3], a);
  digitalWrite(bar[2], b);
  digitalWrite(bar[1], c);
  digitalWrite(bar[0], d);
}

void barrido(byte B) {
  switch (B) {
    case 0: barr(0, 0, 0, 1); break;
    case 1: barr(0, 0, 1, 0); break;
    case 2: barr(0, 1, 0, 0); break;
    case 3: barr(1, 0, 0, 0); break;
  }
}