const int numLEDs = 4;
const int GPIO_Pins[] = {2,3,4,5};
const int runRate = 500;
void setup() {
  // put your setup code here, to run once:
  for (int led = 0; led < numLEDs; led++)
  {
    pinMode(GPIO_Pins[led], OUTPUT);
  }
}
void loop() {
  // put your main code here, to run repeatedly:
  runningLEDs(runRate);

}
void runningLEDs(int runRate)
{
  for (int led = 0; led < numLEDs; led++)
  {
    digitalWrite(GPIO_Pins[led], HIGH);
    delay(runRate);
    digitalWrite(GPIO_Pins[led], LOW);
   // delay(runRate);
  }
}