int a = 7;
int b = 6;
int f = 8;
int g = 9;
int dp = 2;
int c = 3;
int d = 4;
int e = 5;
int btn = 13;
int x = 0;
int y = 0;

void on_segment(int a1,int b1,int c1,int d1,int dp1,int e1,int f1,int g1){
    digitalWrite(a, a1);
    digitalWrite(b, b1);
    digitalWrite(c, c1);
    digitalWrite(d, d1);
    digitalWrite(dp, dp1);
    digitalWrite(e, e1);
    digitalWrite(f, f1);
    digitalWrite(g, g1);
}


void setup() {
  pinMode(a, OUTPUT);
  pinMode(b, OUTPUT);
  pinMode(c, OUTPUT);
  pinMode(d, OUTPUT);
  pinMode(dp, OUTPUT);
  pinMode(e, OUTPUT);
  pinMode(f, OUTPUT);
  pinMode(g, OUTPUT);
  pinMode(btn, INPUT_PULLUP);
  Serial.begin(9600);
}

void loop() {
  
  if (y == 0) {
    x++;
    delay(400);
  }
  Serial.println(x);
  
  if (x == 1) {
    on_segment(1,1,1,1,1,1,1,0); // 0
  }
  else if(x == 2) {
    on_segment(0,1,1,0,0,0,0,0); // 1
  }
  else if(x == 3) {
    on_segment(1,1,0,1,1,1,0,1); // 2
  }
  else if(x == 4) {
    on_segment(1,1,1,1,1,0,0,1); // 3
  }
  else if(x == 5) {
    on_segment(0,1,1,0,1,0,1,1); // 4
  }
  else if(x == 6) {
    on_segment(1,0,1,1,1,0,1,1); // 5
  }
  else if(x == 7) {
    on_segment(1,0,1,1,1,1,1,1); // 6
  }
  else if(x == 8) {
    on_segment(1,1,1,0,1,0,0,0); // 7
  }
  else if(x == 9) {
    on_segment(1,1,1,1,1,1,1,1); // 8
  }
  else if(x == 10) {
    on_segment(1,1,1,1,1,0,1,1); // 9 
  }
  else if(x == 11) {
    on_segment(1,1,1,1,1,1,1,1); // 8
  }
  else if(x == 12) {
    on_segment(1,1,1,0,1,0,0,0); // 7
  }
  else if(x == 13) {
    on_segment(1,0,1,1,1,1,1,1); // 6
  }
  else if(x == 14) {
    on_segment(1,0,1,1,1,0,1,1); // 5
  }
   else if(x == 15) {
    on_segment(0,1,1,0,1,0,1,1); // 4
  }
   else if(x == 16) {
    on_segment(1,1,1,1,1,0,0,1); // 3
  }
  else if(x == 17) {
    on_segment(1,1,0,1,1,1,0,1); // 2
  }
  else if(x == 18) {
    on_segment(0,1,1,0,0,0,0,0); // 1
  }
  if (x == 19) {
    on_segment(1,1,1,1,1,1,1,0); // 0
    x=0;
  }

}