const float beta=3950; //beta coefficiant of the thermistor
int reading; // variable to store senzor reading
float v; // variable to store senzor reading in voltage
float temp; // variable to store senzor reading in celcius
int yellow=12;int green=8;int red=2; // variable for LEDS
void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600); // start of a searial monitor
  pinMode(yellow, OUTPUT);pinMode(green, OUTPUT); // changing the pin mode into output mode
  pinMode(red, OUTPUT);
}
void loop() {
  // put your main code here, to run repeatedly:
  reading=analogRead(A4); //reading the senzor value
  // converting reading into celcius
  temp=1 / (log(1 / (1023. / reading - 1)) / beta + 1.0 / 298.15) - 273.15;
  Serial.print("The temperature is ");  Serial.print(temp);
  Serial.println("℃");
  if(temp>30){
    Serial.println("The temperature is high");
    digitalWrite(green,LOW);
    digitalWrite(yellow, LOW);
    digitalWrite(red, HIGH);
    delay(150);
  }
   
  else if(temp>=25){
    Serial.println("The temperature is optimum");
    digitalWrite(red, LOW);
    digitalWrite(yellow, LOW);
    digitalWrite(green, HIGH);
    delay(120);
    }
  else{
    Serial.println("The temperature is low");
    digitalWrite(red, LOW);
    digitalWrite(green, LOW);
    digitalWrite(yellow, HIGH);
    delay(120);
  }
  delay(1000);
 }