const int buzzerPin = 9;
int inpin=2;


const int songLengthAmazingGrace = 33;



char notesAmazingGrace[]  = "gCECEDCaggCECEDGEGECEDCaggCECEDC ";


int beatsAmazingGrace[] = {2,4,1,1,4,2,4,2,4,2,4,1,1,4,2,10,2,4,1,1,4,2,4,2,4,2,4,1,1,4,2,8,8};


int tempo = 300;

void setup() 
{
  pinMode(buzzerPin, OUTPUT);
  pinMode(inpin, INPUT);
}


void loop() 
{
  if (digitalRead(inpin)==HIGH)
  {
    play_music();
  }
}
  
void play_music()
{
  int i, duration;

  for (i = 0; i < songLengthAmazingGrace; i++) 
  {
    duration = beatsAmazingGrace[i] * tempo; 
    
    if (notesAmazingGrace[i] == ' ')        
    {
      delay(duration);   
    } 
    else                          
    {
      tone(buzzerPin, frequency(notesAmazingGrace[i]), duration);
      
      delay(duration);            
     
    }
    delay(tempo/10);              
  }
}
int frequency(char note) 
{
  int i;
  const int numNotes = 14;  
  
  char names[] = { 'c', 'd', 'e', 'f', 'g', 'a', 'b', 'C', 'D', 'E', 'F', 'G', 'A', 'B' };

  int frequencies[] = {131, 147, 165, 175, 196, 220, 247, 262, 294, 330, 349, 392, 440, 494};
  
  for (i = 0; i < numNotes; i++) 
  {
    if (names[i] == note)      
    {

      return(frequencies[i]);     

    }
  }
  
  
  return(0);  
}