#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);

float criticalTemp = 75;
float currentTemp;
const int led_pin = 9;

const float BETA = 3950; // should match the Beta Coefficient of the thermistor

void setup() {
  Serial.begin(9600);
  pinMode(led_pin, OUTPUT);
  lcd.init();
}

void loop() {
  int analogValue = analogRead(A0);
  float celsius = 1 / (log(1 / (1023. / analogValue - 1)) / BETA + 1.0 / 298.15) - 273.15;
  Serial.print("Temperature: ");
  Serial.print(celsius);
  Serial.println(" ℃");

  lcd.setCursor(0, 0);
  lcd.println("Temperature:");

  lcd.setCursor(0, 1);
  lcd.println(celsius);

  if(celsius > criticalTemp){
    digitalWrite(led_pin, HIGH);
  }else{
    digitalWrite(led_pin, LOW);
  }
}