const int a = 2;
const int b = 4;
const int c = 5;
const int d = 18;
const int e = 19;
const int f = 21;
const int g = 22;
int DIG1 = 27;
int DIG2 = 26;
int DIG3 = 25;
int DIG4 = 33;



void setup() {
  pinMode(a, OUTPUT);
  pinMode(b, OUTPUT);
  pinMode(c, OUTPUT);
  pinMode(d, OUTPUT);
  pinMode(e, OUTPUT);
  pinMode(f, OUTPUT);
  pinMode(g, OUTPUT);
  pinMode(DIG1, OUTPUT);
  pinMode(DIG2, OUTPUT);
  pinMode(DIG3, OUTPUT);
  pinMode(DIG4, OUTPUT);
}


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


void displayLetter(char letter) {
  clearDisplay();
  switch (letter) {
    case 'S':
      digitalWrite(a, HIGH);
      digitalWrite(c, HIGH);
      digitalWrite(d, HIGH);
      digitalWrite(f, HIGH);
      digitalWrite(g, HIGH);
      break;
    case 'Y':
      digitalWrite(b, HIGH);
      digitalWrite(c, HIGH);
      digitalWrite(d, HIGH);
      digitalWrite(f, HIGH);
      digitalWrite(g, HIGH);
      break;
      case 'A':
      digitalWrite(a, HIGH);
      digitalWrite(b, HIGH);
      digitalWrite(c, HIGH);
      digitalWrite(e, HIGH);
      digitalWrite(f, HIGH);
      digitalWrite(g, HIGH);
      break;
      case 'H':
      digitalWrite(b, HIGH);
      digitalWrite(c, HIGH);
      digitalWrite(e, HIGH);
      digitalWrite(f, HIGH);
      digitalWrite(g, HIGH);
      break;

  }
}

void loop() {
  for( int x=0;x<100;x++){
  clearDisplay();
  digitalWrite(DIG1,0);
  digitalWrite(DIG2,1);
  digitalWrite(DIG3,1);
  digitalWrite(DIG4,1);
  displayLetter('S');
  delay(10); 
  clearDisplay();
  digitalWrite(DIG1,1);
  digitalWrite(DIG2,0);
  digitalWrite(DIG3,1);
  digitalWrite(DIG4,1);
  displayLetter('Y');
  delay(10);
  clearDisplay();
  digitalWrite(DIG1,1);
  digitalWrite(DIG2,1);
  digitalWrite(DIG3,0);
  digitalWrite(DIG4,1);
  displayLetter('A');
  delay(10);
  clearDisplay();
  digitalWrite(DIG1,1);
  digitalWrite(DIG2,1);
  digitalWrite(DIG3,1);
  digitalWrite(DIG4,0);
  displayLetter('H');
delay(10);
}
 for( int x=0;x<100;x++){
  clearDisplay();
  digitalWrite(DIG1,0);
  digitalWrite(DIG2,1);
  digitalWrite(DIG3,1);
  digitalWrite(DIG4,1);
  displayLetter('H');
  delay(10); 
  clearDisplay();
  digitalWrite(DIG1,1);
  digitalWrite(DIG2,0);
  digitalWrite(DIG3,1);
  digitalWrite(DIG4,1);
  displayLetter('A');
  delay(10);
  clearDisplay();
  digitalWrite(DIG1,1);
  digitalWrite(DIG2,1);
  digitalWrite(DIG3,0);
  digitalWrite(DIG4,1);
  displayLetter('Y');
  delay(10);
  clearDisplay();
  digitalWrite(DIG1,1);
  digitalWrite(DIG2,1);
  digitalWrite(DIG3,1);
  digitalWrite(DIG4,0);
  displayLetter('S');
delay(10);
 }

}