int Time; // here we create variable having name "Time" and "Distance" 
int Distance;

void setup() {
  // put your setup code here, to run once:
pinMode(2, OUTPUT); // output from pin2 of Arduino is supplied to Trig. pin of ultrasonic sensor
pinMode(3, INPUT); // input from pin3 of Arduino is coming to Echo pin of ultrasonic sensor
Serial.begin(9600); // for printing the value of distance in serial monitor we have to start serial communication
pinMode(4, OUTPUT);
pinMode(5, OUTPUT);
pinMode(6, OUTPUT);
pinMode(7, OUTPUT);
pinMode(8, OUTPUT);
pinMode(9, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(2, HIGH); 
delayMicroseconds(10); // PIN No 2 HIGH 10 microseconds
digitalWrite(2, LOW);
delayMicroseconds(5); // PIN No 2 LOW 5 microseconds
digitalWrite(2, HIGH);
delayMicroseconds(10); 

Time = pulseIn(3, HIGH); // Trig. Pin HIGH for 10 microseconds  due to this 10us high pulse transmitter will generate 8 sonic pulse
Distance = 0.0343*Time/2;
Serial.print("Distance from sensor to object is=");
Serial.println(Distance);
delay(1000);

if(Distance>1 && Distance<=35){
  digitalWrite(4, HIGH);
  digitalWrite(5, HIGH);
  digitalWrite(6, HIGH);
  digitalWrite(7, HIGH);
  digitalWrite(8, HIGH);
  digitalWrite(9, HIGH);
}

if(Distance>35 && Distance<=70){
  digitalWrite(4, LOW);
  digitalWrite(5, HIGH);
  digitalWrite(6, HIGH);
  digitalWrite(7, HIGH);
  digitalWrite(8, HIGH);
  digitalWrite(9, HIGH);
}

if(Distance>70 && Distance<=105){
  digitalWrite(4, LOW);
  digitalWrite(5, LOW);
  digitalWrite(6, HIGH);
  digitalWrite(7, HIGH);
  digitalWrite(8, HIGH);
  digitalWrite(9, HIGH);
}

if(Distance>105 && Distance<=140){
  digitalWrite(4, LOW);
  digitalWrite(5, LOW);
  digitalWrite(6, LOW);
  digitalWrite(7, HIGH);
  digitalWrite(8, HIGH);
  digitalWrite(9, HIGH);
}

if(Distance>140 && Distance<=175){
  digitalWrite(4, LOW);
  digitalWrite(5, LOW);
  digitalWrite(6, LOW);
  digitalWrite(7, LOW);
  digitalWrite(8, HIGH);
  digitalWrite(9, HIGH);
}

if(Distance>175 && Distance<=200){
  digitalWrite(4, LOW);
  digitalWrite(5, LOW);
  digitalWrite(6, LOW);
  digitalWrite(7, LOW);
  digitalWrite(8, LOW);
  digitalWrite(9, HIGH);
}

if(Distance>200){
  digitalWrite(4, LOW);
  digitalWrite(5, LOW);
  digitalWrite(6, LOW);
  digitalWrite(7, LOW);
  digitalWrite(8, LOW);
  digitalWrite(9, LOW);
}
}