const int segmentPins[8] = {2, 3, 4, 5, 6, 7, 8, 9};
const int buttonPin = 10;

const byte numbers[10] = {
  B00000010, // 0
  B11111001, // 1
  B01001000, // 2
  B01100000, // 3
  B11011001, // 4
  B10010010, // 5
  B00000010, // 6
  B11111000, // 7
  B00000000, // 8
  B10000000  // 9
};

int buttonState;
int lastButtonState = LOW;
unsigned long lastDebounceTime = 0;
unsigned long debounceDelay = 50;

int displayedNumber = 0;

void setup() {
  for (int i = 0; i < 8; i++) {
    pinMode(segmentPins[i], OUTPUT);
  }
  pinMode(buttonPin, INPUT);  
}

void loop() {
  int reading = digitalRead(buttonPin);  

  if (reading != lastButtonState) {
    lastDebounceTime = millis();
  }

  if ((millis() - lastDebounceTime) > debounceDelay) {
    if (reading != buttonState && reading == HIGH) {
      displayedNumber = (displayedNumber + 1) % 10;
      showNumber(displayedNumber);
    }
    buttonState = reading;
  }

  lastButtonState = reading;
}

void showNumber(int number) {
  for (int i = 0; i < 8; i++) {
    digitalWrite(segmentPins[i], bitRead(numbers[number], i));
  }
}