int D2 = 1;
int D4 = 2;
int D5 = 3;
int D18 = 4;
int D19 = 5;
int D22 = 6;
int D21 = 7;

void setup() {
  // put your setup code here, to run once:
pinMode(D2, OUTPUT);
pinMode(D4, OUTPUT);
pinMode(D5, OUTPUT);
pinMode(D18, OUTPUT);
pinMode(D19, OUTPUT);
pinMode(D22, OUTPUT);
pinMode(D21, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  // To Display "0"
  digitalWrite(D2, HIGH);
  digitalWrite(D4, HIGH);
  digitalWrite(D5, HIGH);
  digitalWrite(D18, HIGH);
  digitalWrite(D19, HIGH);
  digitalWrite(D22, HIGH);
  digitalWrite(D21, LOW);
  delay(1000);
}