// constants won't change
const int BUTTON_PIN = {9,8}; // Arduino pin connected to button's pin
const int LED_PIN [2]   = {10,7}; // Arduino pin connected to LED's pin
// variables will change:
int ledState = LOW;     // the current state of LED
int lastButtonState;    // the previous state of button
int currentButtonState; // the current state of button

void setup() {
  Serial.begin(9600);                // initialize serial
  pinMode(BUTTON_PIN, INPUT_PULLUP); // set arduino pin to input pull-up mode
  
  pinMode(LED_PIN, OUTPUT);          // set arduino pin to output mode

  for(int i=0;i<2;i++){
    pinMode(BUTTON_PIN[i],INPUT_PULLUP);
    pinMode(LED_PIN[i], OUTPUT);          // set arduino pin to output mode

  }
  currentButtonState = digitalRead(BUTTON_PIN);
}

void loop() {
  lastButtonState    = currentButtonState;      // save the last state
  currentButtonState = digitalRead(BUTTON_PIN); // read new state

  if(lastButtonState == HIGH && currentButtonState == LOW) {
    delay(500);
    Serial.println(HIGH);

    // toggle state of LED
    ledState = !ledState;

    // control LED arccoding to the toggled state
    digitalWrite(LED_PIN, ledState); 
  }
}