class sevin_4_leds
{
  private:
    int8_t d[4];
////
  public:
    int8_t  data[10][8] =
    { //十個數量時，八燈炮分別high/low
      {1, 1, 1, 1, 1, 1, 0, 0}, //0
      {0, 1, 1, 0, 0, 0, 0, 0}, //1
      {1, 1, 0, 1, 1, 0, 1, 0}, //2
      {1, 1, 1, 1, 0, 0, 1, 0}, //3
      {0, 1, 1, 0, 1, 1, 0, 0}, //4
      {1, 0, 1, 1, 0, 1, 1, 0}, //5
      {1, 0, 1, 1, 1, 1, 1, 0}, //6
      {1, 1, 1, 0, 0, 1, 0, 0}, //7
      {1, 1, 1, 1, 1, 1, 1, 0}, //8
      {1, 1, 1, 1, 0, 1, 1, 0}  //9
    };
//
    int8_t pins[8]; //八燈泡腳位代號
    int8_t coms[4]; //四燈接地角位代號
    void set_datapins(int8_t a, int8_t b, int8_t c, int8_t d, int8_t e, int8_t f, int8_t g, int8_t h)
    {
      pins[0] = a; //a號燈
      pins[1] = b; //b號燈
      pins[2] = c; //c號燈
      pins[3] = d; //d號燈
      pins[4] = e; //e號燈
      pins[5] = f; //f號燈
      pins[6] = g; //g號燈
      pins[7] = h; //h號燈
    }
    void set_compins(int8_t A, int8_t B, int8_t C, int8_t D)
    {
      coms[0] = A; //13號位 千位的com
      coms[1] = B; //12號位 百位的com
      coms[2] = C; //11號位 十位的com
      coms[3] = D; //10號位 個位的com
    }
//
    void init() //設定角位為輸出
    {
      for (int i = 0; i <= 7; i++)
        pinMode(pins[i], OUTPUT);
      for (int j = 0; j <= 3; j++)
        pinMode(coms[j], OUTPUT);
    }
//
    void set_digits(int val) //分離四位數字
    {
      d[0] = val / 1000;     //千位數
      d[1] = val / 100 % 10; //百位數
      d[2] = val / 10 % 10;  //十位數
      d[3] = val % 10;       //個位數
    }
//
    void output() //執行發亮
    {
      for (int i = 0; i <= 3; i++) //依次四個位數
      {
        for (int j = 0; j <= 7; j++) //每個位數的八個登
        {
          int k = d[i]; //i=0(k=千位的數字) i=1(k=百位的數字) i=2(k=十位的數字) i=3(k=個位的數字)
          digitalWrite( pins[j], data[k][j] );  //把第K位數的a到h號燈的亮暗寫入角位(四個燈會同步)
        }
        digitalWrite( coms[i], LOW ); //控制單一該位數亮
        delay(20); //持續亮
        digitalWrite( coms[i], HIGH ); //關閉該位數的亮，i++進到下一位數
      }
    }
    void turn_off() //一開始全暗
    {
      for(int i=0; i<=3; i++)
        digitalWrite( coms[i] , HIGH );
    }
};
//
sevin_4_leds number; //宣告四位數
int count = 0; //老師打的，不知道要欉三小
int val = 0; //要顯示的數字
//
void setup()
{
  Serial.begin(9600);
  Serial.print("go");
  number.init();
  number.set_datapins(2, 3, 4, 5, 6, 7, 8, 9);
  number.set_compins(13, 12, 11, 10);
  number.turn_off();
}
//
void loop()
{
  if ( Serial.available() > 0 )
  {
    val = Serial.parseInt();
    Serial.println(val);
    number.set_digits(val);
  }
  number.output();
}