const int LED_RED = 5;
const int LED_GREEN = 4;
const int LED_BLUE = 3;
const int BUTTON = 2;

int curButton = LOW;
int lastButton = LOW;

int countPress = 0;

int debounce(const int last)
{
  int current = digitalRead(BUTTON);
  if (current != last)
  {
    delay(5);
    current = digitalRead(BUTTON);
  }
  return current;
}

void switchLedState(const int countPress)
{
  switch (countPress) {
    case 1:
      {
        digitalWrite(LED_RED, HIGH);
        digitalWrite(LED_GREEN, LOW);
        digitalWrite(LED_BLUE, LOW);
        break;
      }
    case 2:
      {
        digitalWrite(LED_RED, HIGH);
        digitalWrite(LED_GREEN, HIGH);
        digitalWrite(LED_BLUE, LOW);
        break;
      }
    case 3:
      {
        digitalWrite(LED_RED, HIGH);
        digitalWrite(LED_GREEN, HIGH);
        digitalWrite(LED_BLUE, HIGH);
        break;
      }
    case 4:
      {
        digitalWrite(LED_RED, HIGH);
        digitalWrite(LED_GREEN, LOW);
        digitalWrite(LED_BLUE, HIGH);
        break;
      }
    case 5:
      {
        digitalWrite(LED_RED, LOW);
        digitalWrite(LED_GREEN, HIGH);
        digitalWrite(LED_BLUE, LOW);
        break;
      }
    case 6:
      {
        digitalWrite(LED_RED, LOW);
        digitalWrite(LED_GREEN, HIGH);
        digitalWrite(LED_BLUE, HIGH);
        break;
      }
    case 7:
      {
        digitalWrite(LED_RED, LOW);
        digitalWrite(LED_GREEN, LOW);
        digitalWrite(LED_BLUE, HIGH);
        break;
      }
    default:
      {
        digitalWrite(LED_RED, LOW);
        digitalWrite(LED_GREEN, LOW);
        digitalWrite(LED_BLUE, LOW);
        break;
      }
  }
}

void setup() {
  // put your setup code here, to run once:
  pinMode(LED_RED, OUTPUT);
  pinMode(LED_GREEN, OUTPUT);
  pinMode(LED_BLUE, OUTPUT);
  digitalWrite(LED_RED, LOW);

  pinMode(BUTTON, INPUT);
  digitalWrite(BUTTON, LOW);
}

void loop() {
  // put your main code here, to run repeatedly:
  curButton = debounce(lastButton);
  if (curButton == HIGH && lastButton == LOW)
  {
    ++countPress;
    switchLedState(countPress);
    if (countPress == 8)
    {
      countPress = 0;
    }
  }
  lastButton = curButton;
}