int photocell = A0;
int speaker = 8;
float freq = 0;

void setup() {
  // put your setup code here, to run once:
  pinMode(speaker, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  int photoread = analogRead(photocell);
  Serial.println(photoread);
  freq = map(photoread, 0, 1023, 100, 1000);

  /*
   * Default - 350 - 650
   * R1 covered- 100-350
   * R2 covered- 650 - 1000
   */
   tone(speaker, freq, 10);

}