#define echoPin 2
#define trigPin 3 
int buzzer = 7;
int maximumRange = 300;
int minimumRange = 00;
long duration,distance;

void setup() {
  Serial.begin(9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(buzzer, OUTPUT);

}

void loop() {
  digitalWrite(trigPin, LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin,HIGH);

distance = duration/58.2;

if (distance >= maximumRange || distance <= minimumRange){
  Serial.println("Di luar jangkauan");
}
if(distance <5){
digitalWrite(11, LOW);
  digitalWrite(10, LOW);
  digitalWrite(9, LOW);
  
}
if(distance >=5 && distance < 15){
  digitalWrite(11, HIGH);
  digitalWrite(10, LOW);
  digitalWrite(9, LOW); 
  tone(buzzer, 200);
  delay(1000);  
  tone(buzzer, 250);
  delay(2000);                  
  noTone(buzzer);                
  
}
if(distance >=15 && distance < 30){
  digitalWrite(11, LOW);
  digitalWrite(10, HIGH);
  digitalWrite(9, LOW);
  
}
if(distance >=30 && distance < 40){
  digitalWrite(11, LOW);
  digitalWrite(10, LOW);
  digitalWrite(9, HIGH);
   tone(buzzer, 200);
  delay(1000);  
  tone(buzzer, 250);
  delay(2000);                  
  noTone(buzzer);
  
}
if(distance >=40 && distance ){
digitalWrite(11, LOW);
  digitalWrite(10, LOW);
  digitalWrite(9, LOW);

}
}