int BUZZER_PIN = 13;
int BUZZER_CHANNEL = 0;
int b1,b2,b3,b4;


void setup() {
  pinMode(5,INPUT_PULLUP);
  pinMode(18,INPUT_PULLUP);
  pinMode(19,INPUT_PULLUP);
  pinMode(2,INPUT_PULLUP);
  ledcAttachPin(BUZZER_PIN, BUZZER_CHANNEL);
}
void loop() {
  b1 = digitalRead(5);
  b2 = digitalRead(18);
  b3 = digitalRead(19);
  b4 = digitalRead(2);
  if (b1== LOW)
  {
      ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_D, 8);
      delay(10);
  }
  else if (b2== LOW)
  {
      ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_A, 8);
      delay(10);
  }
  else if (b3== LOW)
  {
    ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_G, 8);
      delay(10);
  }
  else if (b4== LOW)
  {
    ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_A, 4);
      delay(150);
          ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_B, 5);
      delay(20);
          ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_C, 5);
      delay(20);
          ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_D, 5);
      delay(20);
          ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_E, 5);
      delay(20);
          ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_A, 3);
      delay(30);
          ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_C, 5);
      delay(20);
          ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_C, 6);
      delay(20);
          ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_F, 5);
      delay(30);
          ledcWriteNote(BUZZER_CHANNEL, (note_t)NOTE_G, 5);
      delay(20);
  }

  else
  {
      ledcWrite(0, 0);
      delay(10);
  }
  
}