#include <LiquidCrystal_I2C.h> 
#include <DHT.h> 

#define DHTPIN 8 
#define DHTTYPE DHT22 
#define ALERT_PIN 7   

DHT dht(DHTPIN, DHTTYPE); 
LiquidCrystal_I2C lcd(0x27, 16, 2); 

void setup() { 
  Serial.begin(9600); 
  Serial.println("Temperature Monitoring System"); 
  lcd.begin(16, 2); 
  dht.begin(); 
  pinMode(ALERT_PIN, OUTPUT);   
} 

void loop() { 
  float t = dht.readTemperature(); 
  float h = dht.readHumidity(); 
  delay(1000); 

  lcd.setCursor(0,0); 
  lcd.print("Temp=");  
  lcd.print(t);   
  lcd.print("C");  

  lcd.setCursor(0,1); 
  lcd.print("Humidity=");  
  lcd.print(h);  
  lcd.print("%"); 

  Serial.print("Temp= ");  
  Serial.print(t);  
  Serial.println(" C"); 
  Serial.print("Humidity= ");  
  Serial.print(h);  
  Serial.println(" %"); 

  if (t > 30) {
    digitalWrite(ALERT_PIN, HIGH);  
  } else {
    digitalWrite(ALERT_PIN, LOW);   
  }

  delay(2000);
}