#include <Servo.h>

Servo servo; 
int trigger_pin = 11;
int echo_pin = 12;
int servo_pin = 7;
int r_led_pin = 4;
int g_led_pin = 5;
double distance = 0.0;
int current_led_status = 0;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(trigger_pin, OUTPUT);
  pinMode(echo_pin, INPUT);
  pinMode(r_led_pin, OUTPUT);
  pinMode(g_led_pin, OUTPUT);
  servo.attach(7);
  digitalWrite(r_led_pin, HIGH);
  digitalWrite(g_led_pin, HIGH);
}

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

  distance = pulseIn(echo_pin, HIGH) / 58.00;

  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.print("\n");

  if (distance < 10) {
    servo.write(90);
    for (int i = 0; i < 5; i++) {
      digitalWrite(r_led_pin, LOW);
      delay(50);
      digitalWrite(r_led_pin, HIGH);
      delay(50);
    }
  }
  else {
    servo.write(0);
    digitalWrite(g_led_pin, LOW);
    delay(500);
    digitalWrite(g_led_pin, HIGH);
  }
}