// Define the pins for the ultrasonic sensor
const int trigPin = 12;   // Trig pin of the ultrasonic sensor
const int echoPin = 13;   // Echo pin of the ultrasonic sensor

// Define the pins for the LEDs
const int pin1 = 1;   // Pin for the LED indicating a near object
const int pin2 = 2;    // Pin for the LED indicating a far object
const int pin3 = 3;
const int pin4 = 4;
const int pin5 = 5;
// Variables for ultrasonic sensor
long duration;  // To store the time it takes for the sound wave to return
int distance;   // To store the calculated distance in centimeters

void setup() {
  pinMode(trigPin, OUTPUT);    // Set trig pin as output
  pinMode(echoPin, INPUT);     // Set echo pin as input
  pinMode(pin1, OUTPUT); // Set near LED pin as output
  pinMode(pin2, OUTPUT); // Set far LED pin as output
  pinMode(pin3, OUTPUT);
  pinMode(pin4, OUTPUT);
  pinMode(pin5, OUTPUT);
  
  Serial.begin(9600);  // Initialize serial communication for debugging
}

void loop() {
  // Clear the trigger pin
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  
  // Send a 10 microsecond pulse to the trigger pin
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  // Measure the duration of the echo pulse
  duration = pulseIn(echoPin, HIGH);
  
  // Calculate the distance in centimeters
  distance = duration * 0.034 / 2;
  
  // Print the distance for debugging
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");
  
  // Check the distance and control LEDs accordingly
  
  if (distance <= 100) {
    digitalWrite(pin1, HIGH);
  }
  if (distance <= 80) {
    digitalWrite(pin2, HIGH);
  }
  if (distance <= 60) {
    digitalWrite(pin3, HIGH);
  }
  if (distance <= 45) {
    digitalWrite(pin4, HIGH);
  }
  if (distance <= 30) {
    digitalWrite(pin5, HIGH);
  }
  delay(100);  // Delay before next reading
}