#define PIN_TRIG 2
#define PIN_ECHO 25 
#define LOWLED 18
#define MIDLED 19
#define HIGHLED 21
#define MOTOR 27

unsigned int level =0;

void setup() {
 
  pinMode(LOWLED, OUTPUT);
  pinMode(MIDLED, OUTPUT);
 pinMode(HIGHLED,OUTPUT);
 pinMode(MOTOR, OUTPUT);
 digitalWrite(LOWLED, HIGH);
 digitalWrite(MIDLED,HIGH);
 digitalWrite(HIGHLED,HIGH);
 digitalWrite(MOTOR,LOW);

 Serial.begin(115200);
 pinMode(PIN_TRIG,OUTPUT);
 pinMode(PIN_ECHO, INPUT);
}

void loop(){
  //Start a new measurement:
  digitalWrite(PIN_TRIG,HIGH);
  delayMicroseconds(10);
  digitalWrite(PIN_TRIG,LOW);

  //Read the result:
  int duration = pulseIn(PIN_ECHO,HIGH);
  Serial.print("Distance in CM: ");
  Serial.println(duration/ 58);
  Serial.print("Distance in inches: " );
  Serial.println(duration / 148);

  level=duration / 58;

  if (level<100)
  {        

       digitalWrite(LOWLED, LOW);
       digitalWrite(MOTOR, HIGH);
       digitalWrite(HIGHLED, HIGH);
       digitalWrite(MIDLED,HIGH);

 }
  else if ((level >200)&& (level <400))
  {
     digitalWrite(LOWLED,HIGH);
     digitalWrite(MIDLED,HIGH);
     digitalWrite(MIDLED, LOW);

  }
     else if (level >=400)
     {
       digitalWrite(LOWLED,LOW);
       digitalWrite(MIDLED,HIGH);
       digitalWrite(LOWLED,HIGH);
       digitalWrite(MOTOR, LOW);

     }
     delay(1000);
}