int led=12;
int trig=6;
int echo=7;
int jarak_treshold=100;
int buzzer=8;
int jeda;
int nada1=523;
int nada2=587;
int nada3=659;
int nada4=698;
int nada5=784;
int nada6=880;
int nada7=988;
int nada8=1047;

float durasi,jarak_cm;

void setup() {
  Serial.begin(9600);
    pinMode(led,OUTPUT);
      pinMode(trig,OUTPUT);
        pinMode(echo, INPUT);
        }
        void loop() {
          digitalWrite(trig, HIGH);
            delayMicroseconds(10);
              digitalWrite(trig, LOW);

                durasi=pulseIn(echo, HIGH);
                  jarak_cm = 0.017 * durasi;

                    if(jarak_cm < jarak_treshold){
                        digitalWrite(led, HIGH);
                            tone(buzzer,nada1,500);
                                delay(200);
                                    noTone(buzzer);

                                        tone(buzzer,nada2,500);
                                            delay(200);
                                                noTone(buzzer);

                                                    tone(buzzer,nada3,500);
                                                        delay(200);
                                                            noTone(buzzer);

                                                                tone(buzzer,nada4,500);
                                                                    delay(200);
                                                                        noTone(buzzer);

                                                                            tone(buzzer,nada5,500);
                                                                                delay(200);
                                                                                    noTone(buzzer);

                                                                                        tone(buzzer,nada6,500);
                                                                                            delay(200);
                                                                                                noTone(buzzer);

                                                                                                    tone(buzzer,nada7,500);
                                                                                                        delay(200);
                                                                                                            noTone(buzzer);

                                                                                                                tone(buzzer,nada8,500);
                                                                                                                    delay(200);
                                                                                                                        noTone(buzzer);
                                                                                                                          }
                                                                                                                            else{
                                                                                                                                digitalWrite(led, LOW);
                                                                                                                                  }

                                                                                                                                    Serial.print("distance: ");
                                                                                                                                      Serial.print(jarak_cm);
                                                                                                                                        Serial.println(" cm");

                                                                                                                                          delay(500);
                                                                                                                                          }