int buttonpin1 = 8;
int buttonpin2 = 9;
int led = 7;

int A;
int B;

void setup() {
  pinMode(led, OUTPUT);
  pinMode(buttonpin1, INPUT);
  pinMode(buttonpin2, INPUT);
}

void loop() {
  boolean A = digitalRead(buttonpin1);
  boolean B = digitalRead(buttonpin2);

   // boolean pinOutState = (A & B); //AND

    //boolean pinOutState = !(A | B); //NOR

   //boolean pinOutState = (A & B) | (!A & !B); //XNOR

    // boolean pinOutState = !(A & B); //NAND

   digitalWrite(led,pinOutState);

}