int pinA = 15;
int pinB = 2;
int pinC = 4;
int pinD = 5; 
int pinE = 18;
int pinF = 19; 
int pinG = 21;
int d1 = 33; 

void setup() {

  pinMode(pinA, OUTPUT);
  pinMode(pinB, OUTPUT);
  pinMode(pinC, OUTPUT);
  pinMode(pinD, OUTPUT);
  pinMode(pinE, OUTPUT);
  pinMode(pinF, OUTPUT);
  pinMode(pinG, OUTPUT);


  pinMode(d1, OUTPUT);
  digitalWrite(d1, LOW);  
}

void loop() {
 
  for (int i = 0; i <= 9; i++) {
    displayDigit(i);
    delay(500);  
  }

  for (int i = 9; i >= 0; i--) {
    displayDigit(i);
    delay(500);  
  }
}

void displayDigit(int num) {
  switch (num) {
    case 0:
      digitalWrite(pinA, HIGH);
      digitalWrite(pinB, HIGH);
      digitalWrite(pinC, HIGH);
      digitalWrite(pinD, HIGH);
      digitalWrite(pinE, HIGH);
      digitalWrite(pinF, HIGH);
      digitalWrite(pinG, LOW);
      break;
    case 1:
      digitalWrite(pinA, LOW);
      digitalWrite(pinB, HIGH);
      digitalWrite(pinC, HIGH);
      digitalWrite(pinD, LOW);
      digitalWrite(pinE, LOW);
      digitalWrite(pinF, LOW);
      digitalWrite(pinG, LOW);
      break;
    case 2:
      digitalWrite(pinA, HIGH);
      digitalWrite(pinB, HIGH);
      digitalWrite(pinC, LOW);
      digitalWrite(pinD, HIGH);
      digitalWrite(pinE, HIGH);
      digitalWrite(pinF, LOW);
      digitalWrite(pinG, HIGH);
      break;
    case 3:
      digitalWrite(pinA, HIGH);
      digitalWrite(pinB, HIGH);
      digitalWrite(pinC, HIGH);
      digitalWrite(pinD, HIGH);
      digitalWrite(pinE, LOW);
      digitalWrite(pinF, LOW);
      digitalWrite(pinG, HIGH);
      break;
    case 4:
      digitalWrite(pinA, LOW);
      digitalWrite(pinB, HIGH);
      digitalWrite(pinC, HIGH);
      digitalWrite(pinD, LOW);
      digitalWrite(pinE, LOW);
      digitalWrite(pinF, HIGH);
      digitalWrite(pinG, HIGH);
      break;
    case 5:
      digitalWrite(pinA, HIGH);
      digitalWrite(pinB, LOW);
      digitalWrite(pinC, HIGH);
      digitalWrite(pinD, HIGH);
      digitalWrite(pinE, LOW);
      digitalWrite(pinF, HIGH);
      digitalWrite(pinG, HIGH);
      break;
    case 6:
      digitalWrite(pinA, HIGH);
      digitalWrite(pinB, LOW);
      digitalWrite(pinC, HIGH);
      digitalWrite(pinD, HIGH);
      digitalWrite(pinE, HIGH);
      digitalWrite(pinF, HIGH);
      digitalWrite(pinG, HIGH);
      break;
    case 7:
      digitalWrite(pinA, HIGH);
      digitalWrite(pinB, HIGH);
      digitalWrite(pinC, HIGH);
      digitalWrite(pinD, LOW);
      digitalWrite(pinE, LOW);
      digitalWrite(pinF, LOW);
      digitalWrite(pinG, LOW);
      break;
    case 8:
      digitalWrite(pinA, HIGH);
      digitalWrite(pinB, HIGH);
      digitalWrite(pinC, HIGH);
      digitalWrite(pinD, HIGH);
      digitalWrite(pinE, HIGH);
      digitalWrite(pinF, HIGH);
      digitalWrite(pinG, HIGH);
      break;
    case 9:
      digitalWrite(pinA, HIGH);
      digitalWrite(pinB, HIGH);
      digitalWrite(pinC, HIGH);
      digitalWrite(pinD, HIGH);
      digitalWrite(pinE, LOW);
      digitalWrite(pinF, HIGH);
      digitalWrite(pinG, HIGH);
      break;
  }
}