#define ECHO_PIN 3
#define TRIG_PIN 2
#define LED_M 4
#define LED_K 7
#define LED_H 8
#define pinBuzzer 5
#include <Servo.h>
Servo myservo;
int potpin = 0;
int val;

float readDistanceCM(){
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW );
  int duration = pulseIn(ECHO_PIN, HIGH );
  return duration * 0.034 / 2;
}
void setup() {
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT );
  Serial .begin(115200);
  pinMode(pinBuzzer, OUTPUT);
  pinMode(LED_M, OUTPUT);
  pinMode(LED_K, OUTPUT);
  pinMode(LED_H, OUTPUT);
  myservo.attach(9);

}

void loop() {
  float distance = readDistanceCM();
  Serial.print("Measured distance: ");
  Serial.print (readDistanceCM());
  Serial.println("CM");
  Serial.print("Warning");

  if (distance <= 200){
    myservo.write(90);
    delay(15);
    tone(pinBuzzer,1000);
    digitalWrite(LED_M, HIGH);
    digitalWrite(LED_K, LOW);
    digitalWrite(LED_H, LOW);
    delay(200);
    tone(pinBuzzer, 500);
    delay (200);
    
  }
  else if (distance <=300){
    noTone(pinBuzzer);
    digitalWrite(LED_K, HIGH);
    delay(100);
    digitalWrite(LED_K, LOW);
    delay(200);
    digitalWrite(LED_M, LOW);
    digitalWrite(LED_H, LOW);
    
  }
  else{
    myservo.write (0);
    noTone(pinBuzzer);
    digitalWrite(LED_M, LOW);
    digitalWrite(LED_K, LOW);
    digitalWrite(LED_H, HIGH);
    
  }
}