const int TRIG_PIN = 12;
const int ECHO_PIN = 14;
long duration, distance;
void setup() {
Serial.begin(115200);
pinMode(TRIG_PIN, OUTPUT);
pinMode(ECHO_PIN, INPUT);
pinMode(2, OUTPUT);
pinMode(4, OUTPUT);
pinMode(5, OUTPUT);
}
void loop() {
distance = getDistanceInCentimeters();
Serial.println("Distance = "+ String(distance));
if(distance>100)
{
  digitalWrite(2, HIGH);
  delay(1000);
  digitalWrite(2, LOW);
}
if(distance>200)
{
  digitalWrite(2, HIGH);
  digitalWrite(4, HIGH);
  delay(1000);
  digitalWrite(2, LOW);
  digitalWrite(4, LOW);
}
if(distance>350)
{
  digitalWrite(2, HIGH);
  digitalWrite(4, HIGH);
  digitalWrite(5, HIGH);
  delay(1000);
  digitalWrite(2, LOW);
  digitalWrite(4, LOW);
  digitalWrite(5, LOW);
}
delay(1000);
}
long getDistanceInCentimeters() {
digitalWrite(TRIG_PIN,LOW);
delayMicroseconds(2);
digitalWrite(TRIG_PIN, HIGH);
delayMicroseconds(10);
digitalWrite(TRIG_PIN, LOW);
duration = pulseIn(ECHO_PIN, HIGH);
return (duration * 0.034 / 2) + 1;
}