#define TRIG 9
#define ECHO 10
#define BUZZER 8
#define RED_LED 6
#define GREEN_LED 5

long duration;
int distance;

void setup() {
  pinMode(TRIG, OUTPUT);
  pinMode(ECHO, INPUT);
  pinMode(BUZZER, OUTPUT);
  pinMode(RED_LED, OUTPUT);
  pinMode(GREEN_LED, OUTPUT);
}

void loop() {
  // Trigger ultrasonic sensor
  digitalWrite(TRIG, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG, LOW);

  // Read echo time
  duration = pulseIn(ECHO, HIGH);
  distance = duration * 0.034 / 2; // distance in cm

  if (distance <= 10) {  // Object detected
    digitalWrite(BUZZER, HIGH);     // Buzzer ON
    digitalWrite(RED_LED, HIGH);    // Red LED ON
    digitalWrite(GREEN_LED, LOW);   // Green LED OFF
  } 
  else {                   // No object
    digitalWrite(BUZZER, LOW);      // Buzzer OFF
    digitalWrite(RED_LED, LOW);     // Red LED OFF
    digitalWrite(GREEN_LED, HIGH);  // Green LED ON
  }
}