const int inputPin = 2;
const int outputPin = 3;
const int flashOnTime = 4;
const int flashOffTime = 4;

void setup() {
  pinMode(inputPin, INPUT);
  pinMode(outputPin, OUTPUT);
}

void loop() {
  if (digitalRead(inputPin) == HIGH) {
    digitalWrite(outputPin, HIGH);
    delay(40);
    while (digitalRead(inputPin) == HIGH) {
      digitalWrite(outputPin, HIGH);
      delay(flashOnTime);
      digitalWrite(outputPin, LOW);
      delay(flashOffTime);
    }
  }
  digitalWrite(outputPin, LOW);
}mi