#define trigger 5
#define echo 4
#define Relay 6
int val = 0;
#include "DHT.h"
#define DHTTYPE DHT22 
#define DHTPIN 2

DHT dht(DHTPIN, DHTTYPE);



float time=0,distance=0;

void setup() 
{
Serial.begin(9600);

dht.begin();
 pinMode(trigger,OUTPUT);
 pinMode(echo,INPUT);
 pinMode(Relay,OUTPUT);

 delay(2000);
}

void loop() 

{
  float h = dht.readHumidity();
  measure_distance();
  if(distance<5)
  {
    digitalWrite(Relay,HIGH);
    if(h>20){
      digitalWrite(Relay, LOW);
    }
  }
  else
  {
    digitalWrite(Relay,LOW);
  }

 delay(500);
}

void measure_distance()
{
  digitalWrite(trigger,LOW);
  delayMicroseconds(2);
  digitalWrite(trigger,HIGH);
  delayMicroseconds(10);
  digitalWrite(trigger,LOW);
  delayMicroseconds(2);
  time=pulseIn(echo,HIGH);


 distance=time*200/20000;
}