float temperature;
int pinA0 = 0;

void setup() {
   Serial.begin(9600);
}
void loop() {
   // read analog volt from sensor and save to variable temp
  int analogValue = analogRead(pinA0);
  
   // convert the analog volt to its temperature equivalent _ BETA=3950
  //temperature = 1 / (log(1 / (1023. / analogValue - 1)) / 3950 + 1.0 / 298.15) - 273.15;
  //temperature = (125*analogValue) >> 8;
  digitalWrite(3, HIGH);   // LED de controlo
  if(temperature>=30)
    digitalWrite(4, HIGH);
  else
    digitalWrite(4, LOW);
  if(temperature>=60)
    digitalWrite(5, HIGH);
  else
      digitalWrite(5, LOW); 

   //display temperature value
   Serial.print("TEMPERATURE = ");
   Serial.print(temperature); 
   Serial.print("*C");
   Serial.println();

  delay(50);
}