// sketch 01_03_paperclip
int ledPin = 13;
int switchPin = 7;

void setup()
{
  pinMode(ledPin, OUTPUT);
  pinMode(switchPin, INPUT_PULLUP);
}

void loop()
{
  if (digitalRead(switchPin) == LOW)
  {
    flash(100);
  }
  else
  {
    flash(500);
  }
}

void flash(int delayPeriod)
{
  digitalWrite(ledPin, HIGH);
  delay(delayPeriod);
  digitalWrite(ledPin, LOW);
  delay(delayPeriod);
}