int photoPin = A0;
int buzzPin = 9;
float fixedResistor = 10000.0;
int dt = 1000;

void setup(){
  Serial.begin(9600);
  pinMode(photoPin, INPUT);
  pinMode(buzzPin, OUTPUT);
}

void loop(){
  int photoValue = analogRead(photoPin);

  int frequency = map(photoValue, 0,1023,200,20000);

  tone(buzzPin, frequency);

Serial.print(" Photo Resistor Value = ");
Serial.print(photoValue);
Serial.print(",");
Serial.print(" Sound = ");
Serial.print(frequency);
delay(dt);
}