int echoPin = 3;
int trigPin = 2;
int led1 = 13;
int led2 = 7;
int led3 = 4;

void setup() {
  // put your setup code here, to run once:
pinMode(echoPin, INPUT);
pinMode(trigPin, OUTPUT);
pinMode(led1, OUTPUT);
pinMode(led2, OUTPUT);
pinMode(led3, OUTPUT);
}
float ultrasonic (){
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  int durasipantulan = pulseIn(echoPin,HIGH);
  return durasipantulan * 0.034 / 2;
}

void loop() {
  // put your main code here, to run repeatedly:
float jarak = ultrasonic ();
if (jarak<=5){
 digitalWrite(led1, HIGH);
 digitalWrite(led2, LOW);
 digitalWrite(led3, LOW);
}
else if (jarak<=10 && jarak>5){
  digitalWrite(led2, HIGH);
  digitalWrite(led1, LOW);
  digitalWrite(led3, LOW);
}
else if (jarak>10){
  digitalWrite(led3, HIGH);
  digitalWrite(led2, LOW);
  digitalWrite(led1, LOW);
}
}