#define pinTrig 3 
#define pinEcho 2 
#define pinBuz 13 

long waktu, jarak;

void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
pinMode (pinBuz, OUTPUT);
pinMode (pinTrig, OUTPUT);
pinMode (pinEcho, INPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite (pinTrig, LOW);
delayMicroseconds(2);
digitalWrite (pinTrig, HIGH);
delayMicroseconds(10);
digitalWrite (pinTrig, LOW);

waktu = pulseIn (pinEcho, HIGH);
jarak = waktu / (58.2) ;

if (jarak < 250 && jarak >= 200){
  tone(pinBuz, 100);
  delay (50);
  noTone (pinBuz);
  delay (200);
}

if (jarak < 200 && jarak >= 150){
  tone(pinBuz, 200);
  delay (50);
  noTone (pinBuz);
  delay (150);
}

if (jarak < 150 && jarak >= 100){
  tone(pinBuz, 300);
  delay (50);
  noTone (pinBuz);
  delay (100);
}

if (jarak < 100 && jarak >= 50){
  tone(pinBuz, 400);
  delay (50);
  noTone (pinBuz);
  delay (50);
}

if (jarak < 50 && jarak >= 2){
  tone(pinBuz, 500);
  delay (50);
  noTone (pinBuz);
}

else {
  noTone (pinBuz);
}
}