void setup() {
  pinMode(D0, OUTPUT);
  pinMode(D1, OUTPUT);
  pinMode(D2, OUTPUT);
  pinMode(D3, OUTPUT);
  pinMode(D4, OUTPUT);
}

void loop() {
  digitalWrite(D0, HIGH);   
  delay(20);                       
  digitalWrite(D0, LOW);    
  delay(20);  

  digitalWrite(D1, HIGH);   
  delay(20);                       
  digitalWrite(D1, LOW);    
  delay(20);

  digitalWrite(D2, HIGH);   
  delay(20);                       
  digitalWrite(D2, LOW);    
  delay(20);

  digitalWrite(D3, HIGH);   
  delay(20);                       
  digitalWrite(D3, LOW);    
  delay(20);

  digitalWrite(D4, HIGH);   
  delay(20);                       
  digitalWrite(D4, LOW);    
  delay(20);

  digitalWrite(D3, HIGH);   
  delay(20);                       
  digitalWrite(D3, LOW);    
  delay(20);

  digitalWrite(D2, HIGH);   
  delay(20);                       
  digitalWrite(D2, LOW);    
  delay(20);

  digitalWrite(D1, HIGH);   
  delay(20);                       
  digitalWrite(D1, LOW);    
  delay(20);
}

//@ApePanthiya ICT