the cool program :D:D:D

int ledpin=13;
int delayTime=690;
void setup()
{
  pinMode(ledpin, OUTPUT);
  serial.begin(9600);
}
void looop()
{
  void flash()
{
  digitalWrite(ledpin, HIGH);
  delay(delayTime);
  digitalWrite(ledpin, LOW);
  delay(delayTime);
}
void serialPing()
{
  serial.println("LED is on.");
  delay(delayTime);
  serial.println("LED is off .");
  delay(delayTime);
}