#include "DHT.h"
#define DHT_PIN 4 // The Arduino Nano pin connected to DHT22 sensor
#define DHT_TYPE DHT22
DHT dht22(DHT_PIN, DHT_TYPE);
void setup() {
  Serial.begin(9600);
  dht22.begin(); // initialize the sensor
}
void loop() {
  // wait a few seconds between measurements.
  delay(2000);
  // read humidity
  float humi = dht22.readHumidity();
  // read temperature as Celsius
  float temperature_C = dht22.readTemperature();
  // read temperature as Fahrenheit
  float temperature_F = dht22.readTemperature (true);
  
  // check if any reads failed
  if (isnan (humi) || isnan (temperature_C) || isnan (temperature_F)) { 
    Serial.println("Failed to read from DHT sensor!");
  } else {
    Serial.print("Humidity: ");
    Serial.print(humi);
    Serial.print("%");
    Serial.print(" | ");
    Serial.print("Temperature: ");
    Serial.print(temperature_C);
    Serial.print("°C ~ ");
    Serial.print(temperature_F);
    Serial.println("°F");
  }
}