const int ledPin = 13;
const int buttonPin = 2;

long time;
int ledStat;
int flashTime;

void setup()
{
  pinMode(ledPin,OUTPUT);
  flashTime=1000;
  time=-flashTime;
  ledStat = HIGH;

  pinMode(buttonPin,INPUT_PULLUP);
  pinMode(4,OUTPUT);
}

void loop()
{
  if((millis()-time)>=flashTime)
  {
    if(ledStat==HIGH)ledStat=LOW;
    else ledStat=HIGH;
    digitalWrite(ledPin, ledStat);
    time=millis();
  }

  if(digitalRead(buttonPin)==HIGH)
  {
    digitalWrite(4, LOW);
    flashTime=1000;
  }
  else
  {
    digitalWrite(4, HIGH);
    flashTime=250;
  }
}