const int trigPin=2;
const int echoPin=3;

const int nearLedPin=13;
const int farLedPin=12;

long duration;
int distance;
void setup(){
 pinMode(trigPin, OUTPUT); // put your setup code here, to run once:
 pinMode(echoPin, INPUT);
 pinMode(farLedPin, OUTPUT);

 Serial.begin(9600);

}
void loop(){
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);

 digitalWrite(trigPin, HIGH);
 delayMicroseconds(10);
 digitalWrite(trigPin, LOW);

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


 Serial.print("Distance:");
 Serial.print(distance);
 Serial.println("cm");
 if(distance<=50){
  digitalWrite(nearLedPin, HIGH);
  digitalWrite(farLedPin, LOW);
 }else{
  digitalWrite(nearLedPin, LOW);
  digitalWrite(farLedPin, HIGH);
 }
  delay(100);
}