Mini Piano V1.0

Mini Piano V1.0(Arduino)

int speaker = 13;
int button_1 = 0;
int button_2 = 1;
int button_3=2;
int button_4 = 3;
int button_5 = 4;
int button_6=5;
int button_7=6;
int button_8=7;
int button_9=8;
int button_10=9;
int button_11=10;
int button_12=11;
int button_13=12;

// the setup routine runs once when you press reset:
void setup() {                
  // initialize the digital pin as an output.
 
  pinMode(speaker,OUTPUT);
pinMode(0,INPUT);
pinMode(1,INPUT);
pinMode(2,INPUT);
pinMode(3,INPUT);
pinMode(4,INPUT);
pinMode(5,INPUT);
pinMode(6,INPUT);
pinMode(7,INPUT);
pinMode(8,INPUT);
pinMode(9,INPUT);
pinMode(10,INPUT);
pinMode(11,INPUT);
pinMode(12,INPUT);
digitalWrite(0,HIGH);
digitalWrite(1,HIGH);
digitalWrite(2,HIGH);
digitalWrite(3,HIGH);
digitalWrite(4,HIGH);
digitalWrite(5,HIGH);
digitalWrite(6,HIGH);
digitalWrite(7,HIGH);
digitalWrite(8,HIGH);
digitalWrite(9,HIGH);
digitalWrite(10,HIGH);
digitalWrite(11,HIGH);
digitalWrite(12,HIGH);
noTone(13);
}

// the loop routine runs over and over again forever:
void loop() {
  if(digitalRead(0) == LOW)
     {tone(13,262);
     }
    else  if(digitalRead(1) == LOW)
     {tone(13,294);
     }
      else  if(digitalRead(2) == LOW)
     {tone(13,330);
     }
      else  if(digitalRead(3) == LOW)
     {tone(13,349);
     }
      else  if(digitalRead(4) == LOW)
     {tone(13,392);
     }
     else  if(digitalRead(5) == LOW)
     {tone(13,440);
     }
     else  if(digitalRead(6) == LOW)
     {tone(13,494);
     }
      else  if(digitalRead(7) == LOW)
     {tone(13,523);
     }
     else  if(digitalRead(8) == LOW)
     {tone(13,277);
     }
      else  if(digitalRead(9) == LOW)
     {tone(13,311);
     }
     else  if(digitalRead(10) == LOW)
     {tone(13,370);
     }
      else  if(digitalRead(11) == LOW)
     {tone(13,415);
     }
      else  if(digitalRead(12) == LOW)
     {
       tone(13,466);
     }
     else
     {
       noTone(13);
     }
 
     
}