const int sensorPin = A0;
const float baselineTemp= 201;
// I set the sensor temperature to 205 degrees, then:
//When the constant is set to a higher temperature than the sensor, we find that the three LEDs are off
//When the constant is set to a temperature three degrees lower than the sensor, one lights up
//When the constant is set to a temperature four degrees lower than the sensor, two lights up
//When the constant is set to a temperature six degrees lower than the sensor, all three lights up


void setup() {
  Serial.begin(1000);

  for(int pinNumber=2; pinNumber<5; pinNumber++) {
        pinMode(pinNumber, OUTPUT);
        digitalWrite(pinNumber, LOW);
    }
}


void loop() {
  int sensorVal=analogRead(sensorPin);
  Serial.print("Sensor value : ");
  Serial.println(sensorVal);

  float voltage = (sensorVal/1024.0) * 5.0;
  Serial.print("Volts : ");
  Serial.println(voltage);

  float temp = (voltage-0.5) * 100;
  Serial.print("Degrees C : ");
  Serial.println(temp);
  Serial.println("-----------------------------------------------------");

  if(temp<baselineTemp){
    digitalWrite(2, LOW);
    digitalWrite(3, LOW);
    digitalWrite(4, LOW);
  }
else if(temp >= baselineTemp+2 && temp < baselineTemp+4) {
digitalWrite(2, HIGH);
digitalWrite(3, LOW);
digitalWrite(4,LOW);
}else if(temp >= baselineTemp+4 && temp < baselineTemp+6) {
digitalWrite(2, HIGH);
digitalWrite(3, HIGH);
digitalWrite(4, LOW);
}else if(temp >= baselineTemp+6) {
digitalWrite(2, HIGH);
digitalWrite(3, HIGH);
digitalWrite(4, HIGH);
}
delay(1000);


}