int a=0,b=1,c=19,d=18,e=17,f=16,g=15;
void setup() {
  pinMode(a, OUTPUT);
  pinMode(b, OUTPUT);
  pinMode(c, OUTPUT);
  pinMode(d, OUTPUT);
  pinMode(e, OUTPUT);
  pinMode(f, OUTPUT);
  pinMode(g, OUTPUT);

}
void eight (){
    digitalWrite(a , HIGH);
  digitalWrite(b , HIGH);
  digitalWrite(c , HIGH);
  digitalWrite(d , HIGH);
  digitalWrite(e , HIGH);
  digitalWrite(f , HIGH);
  digitalWrite(g , HIGH);
}

void zero (){
  digitalWrite(a , HIGH);
  digitalWrite(b , HIGH);
  digitalWrite(c , HIGH);
  digitalWrite(d , HIGH);
  digitalWrite(e , HIGH);
  digitalWrite(f , HIGH);
  digitalWrite(g , LOW);
}
void one (){
  digitalWrite(a , LOW);
  digitalWrite(b , HIGH);
  digitalWrite(c , HIGH);
  digitalWrite(d , LOW);
  digitalWrite(e , LOW);
  digitalWrite(f , LOW);
  digitalWrite(g , LOW);
}
void two (){
  digitalWrite(a , HIGH);
  digitalWrite(b , HIGH);
  digitalWrite(c , LOW);
  digitalWrite(d , HIGH);
  digitalWrite(e , HIGH);
  digitalWrite(f , LOW);
  digitalWrite(g , HIGH);
}
void three (){
  digitalWrite(a , HIGH);
  digitalWrite(b , HIGH);
  digitalWrite(c , HIGH);
  digitalWrite(d , HIGH);
  digitalWrite(e , LOW);
  digitalWrite(f , LOW);
  digitalWrite(g , HIGH);
}
void four (){
  digitalWrite(a , LOW);
  digitalWrite(b , HIGH);
  digitalWrite(c , HIGH);
  digitalWrite(d , LOW);
  digitalWrite(e , LOW);
  digitalWrite(f , HIGH);
  digitalWrite(g , HIGH);
}
void five(){
  digitalWrite(a , HIGH);
  digitalWrite(b , LOW);
  digitalWrite(c , HIGH);
  digitalWrite(d , HIGH);
  digitalWrite(e , LOW);
  digitalWrite(f , HIGH);
  digitalWrite(g , HIGH);
}
void six(){
  digitalWrite(a , HIGH);
  digitalWrite(b , LOW);
  digitalWrite(c , HIGH);
  digitalWrite(d , HIGH);
  digitalWrite(e , HIGH);
  digitalWrite(f , HIGH);
  digitalWrite(g , HIGH);
}
void seven(){
  digitalWrite(a , HIGH);
  digitalWrite(b , HIGH);
  digitalWrite(c , HIGH);
  digitalWrite(d , LOW);
  digitalWrite(e , LOW);
  digitalWrite(f , LOW);
  digitalWrite(g , LOW);
}

void nine(){
  digitalWrite(a , HIGH);
  digitalWrite(b , HIGH);
  digitalWrite(c , HIGH);
  digitalWrite(d , LOW);
  digitalWrite(e , LOW);
  digitalWrite(f , HIGH);
  digitalWrite(g , HIGH);
}


void loop() {
  zero();
  delay(500);
  one();
  delay(500);
  two();
  delay(500);
  three();
  delay(500);
  four();
  delay(500);
  five();
  delay(500);
  six();
  delay(500);
  seven();
  delay(500);
  eight();
  delay(500);
  nine();
  delay(500);
}