#include<Arduino.h>
#include<LiquidCrystal.h>

LiquidCrystal lcd(10, 9, 8, 7, 6, 5);

#define Trig_pin 13
#define Echo_pin 12
#define LED_pin 11

void setup()
 {
  
  lcd.begin(16, 2);

  Serial.begin(115200);
  pinMode(Trig_pin, OUTPUT);
  pinMode(Echo_pin, INPUT);
  pinMode(LED_pin, OUTPUT);

}

void loop() {

  digitalWrite(Trig_pin, LOW);
  delayMicroseconds(3);
  digitalWrite(Trig_pin, HIGH);
  delayMicroseconds(12);
  digitalWrite(Trig_pin, LOW);

  long duration = pulseIn(Echo_pin, HIGH);
  long distance = duration * 0.034/2;

  lcd.print("Distance");
  lcd.print(distance);
  lcd.println("cm");

  Serial.print("Distance:");
  Serial.print(distance);
  Serial.println("cm");

  if(distance == 4){
    digitalWrite(LED_pin, HIGH);
  }
  else{
    digitalWrite(LED_pin, LOW);
  }

  delay(1000);

}