const int buttonPin = 4;
int buttonState =  0;

void setup() {

  pinMode(3, OUTPUT);
  pinMode(buttonPin, INPUT);
  // put your setup code here, to run once:
}

void loop() {
  buttonState = digitalRead(buttonPin);
  if (buttonState == HIGH) {
  //turn LED on:  
  digitalWrite(3, HIGH); //turn the LED on HIGH is the voltage
  delay(100);
  digitalWrite(3, LOW);
  delay(100);
  
 } else {
  
  //turn LED off
   digitalWrite(3, HIGH); //turn the LED on HIGH is the voltage
  delay(1000);
  digitalWrite(3, LOW);
  delay(1000); 
  
 }

}