const uint8_t countInputPins = 4; 
const uint8_t inputPinsArray[countInputPins] {2,3,4,5};
const uint8_t outputPin = 6;

void setup() {
  for (uint8_t i = 0; i < countInputPins; i ++) 
    pinMode(inputPinsArray[i], INPUT_PULLUP);
  pinMode(outputPin, OUTPUT);
}

void loop() {
  static uint8_t value = 0;
  static uint8_t oldValue = 0;
  
  for (uint8_t i = 0; i < countInputPins; i ++) 
    bitWrite(value, i, digitalRead(inputPinsArray[i]));
  
  if (value != oldValue) {
    switch (value) {
      case 5:
        digitalWrite(outputPin, LOW);
      break;
      case 10:
        digitalWrite(outputPin, HIGH);
      break;
    }
    oldValue = value;
  }

  delay(10);
}