const int buttonPin = 12;
const int ledPin = 11;

int buttonState = 0;
int status = 0;

void setup() {
  // put your setup code here, to run once:

   pinMode(ledPin, OUTPUT);
   pinMode(buttonPin, INPUT_PULLUP);


}

void loop() {
  //READ BUTTON STSATE,  

  buttonState = digitalRead(buttonPin);

  // if button pressed....

   if (buttonState == LOW)
   {
      // CHECK IF LED IS OFF
     if ( status == 0)
     {

       digitalWrite(ledPin, HIGH);
        status = 1;

     }

     else if ( status == 1)
     {

         digitalWrite(ledPin, LOW);

          status = 0;
     }

   }
       delay(100);
}