#define trigPin 7
#define echoPin 6
#define ledbiru 8
#define ledhijau 9
#define ledkuning 10
#define ledmerah 11

void setup() {
  Serial.begin (9600);
    pinMode(trigPin, OUTPUT);
      pinMode(echoPin, INPUT);
        pinMode(ledbiru, OUTPUT);
          pinMode(ledhijau, OUTPUT);
            pinMode(ledkuning, OUTPUT);
              pinMode(ledmerah, OUTPUT);
              }

              void loop() {
                long duration, distance;
                  digitalWrite(trigPin, LOW); 
                    delayMicroseconds(2);
                      digitalWrite(trigPin, HIGH);
                        delayMicroseconds(10);
                          digitalWrite(trigPin, LOW);
                            duration = pulseIn(echoPin, HIGH);
                              distance = (duration/2) / 29.1;
                                if (distance >= 16){
                                    digitalWrite(ledbiru, HIGH);
                                        digitalWrite(ledhijau, LOW);
                                            digitalWrite(ledkuning, LOW);
                                                digitalWrite(ledmerah,LOW);
                                                  }
                                                    else {
                                                        digitalWrite(ledbiru,LOW);
                                                          }
                                                            if (distance <= 15){
                                                                digitalWrite(ledhijau, HIGH);
                                                                    digitalWrite(ledkuning, LOW);
                                                                        digitalWrite(ledmerah,LOW);
                                                                          }
                                                                            if (distance < 10) {
                                                                                digitalWrite(ledkuning, HIGH);
                                                                                    digitalWrite(ledhijau, LOW);
                                                                                        digitalWrite(ledmerah,LOW); 
                                                                                          }
                                                                                            if (distance < 5) {
                                                                                                digitalWrite(ledmerah, HIGH);
                                                                                                    digitalWrite(ledkuning, LOW);
                                                                                                        digitalWrite(ledhijau, LOW);
                                                                                                          }
                                                                                                            delay(500);
                                                                                                            }