pongLed.ino

int curr = 0;

void setup() {
    for (int i=0; i<5; i++){
      pinMode(i, OUTPUT);
    }
    digitalWrite(4, HIGH);
    delay(5000);
}
void loop() {
    digitalWrite(4, LOW);
    digitalWrite (0, HIGH && (curr & B00001000));
    digitalWrite (1, HIGH && (curr & B00000100));
    digitalWrite (2, HIGH && (curr & B00000010));
    digitalWrite (3, HIGH && (curr & B00000001));
    curr += 1;
    curr = curr % 10;
    delay(1000);
    digitalWrite(4, HIGH);
}