Arduino Button

const int buttonPin = 8;
const int ledPin = 12;
int state = 0;

void setup() {

  Serial.begin(9600);
  pinMode(ledPin, OUTPUT);
  pinMode(buttonPin, INPUT);

}

void loop() {

  if ( digitalRead(buttonPin) == HIGH && state == 0 )
    {

      digitalWrite(ledPin, HIGH);
      state = 1;

    }
  if( digitalRead(buttonPin) == HIGH && state == 1 )
    {

      digitalWrite(ledPin, LOW);
      state = 0;

    }

}