const int trigPin1 = 9;
const int echoPin1 = 10;
const int trigPin2 = 11;
const int echoPin2 = 12;

const int ledRed1 = 2;
const int ledYellow1 = 3;
const int ledGreen1 = 4;

const int ledRed2 = 5;
const int ledYellow2 = 6;
const int ledGreen2 = 7;

long duration;
int distance;

void setup() {
  // Set up the serial communication
  Serial.begin(9600);

  // Set up the ultrasonic sensors
  pinMode(trigPin1, OUTPUT);
  pinMode(echoPin1, INPUT);
  pinMode(trigPin2, OUTPUT);
  pinMode(echoPin2, INPUT);

  // Set up the LEDs
  pinMode(ledRed1, OUTPUT);
  pinMode(ledYellow1, OUTPUT);
  pinMode(ledGreen1, OUTPUT);
  pinMode(ledRed2, OUTPUT);
  pinMode(ledYellow2, OUTPUT);
  pinMode(ledGreen2, OUTPUT);
}

void loop() {
  // Measure distance from sensor 1
  distance = measureDistance(trigPin1, echoPin1);
  Serial.print("Sensor 1: ");
  Serial.print(distance);
  Serial.println(" cm");
  controlLEDs(distance, ledRed1, ledYellow1, ledGreen1);

  // Measure distance from sensor 2
  distance = measureDistance(trigPin2, echoPin2);
  Serial.print("Sensor 2: ");
  Serial.print(distance);
  Serial.println(" cm");
  controlLEDs(distance, ledRed2, ledYellow2, ledGreen2);

  delay(500);
}

int measureDistance(int trigPin, int echoPin) {
  // Clear the trigPin
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);

  // Set the trigPin high for 10 microseconds
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // Read the echoPin
  duration = pulseIn(echoPin, HIGH);

  // Calculate the distance
  int distance = duration * 0.034 / 2;

  return distance;
}

void controlLEDs(int distance, int ledRed, int ledYellow, int ledGreen) {
  // Turn off all LEDs
  digitalWrite(ledRed, LOW);
  digitalWrite(ledYellow, LOW);
  digitalWrite(ledGreen, LOW);

  // Turn on the appropriate LED based on the distance
  if (distance < 10) {
    digitalWrite(ledRed, HIGH);
  } else if (distance < 20) {
    digitalWrite(ledYellow, HIGH);
  } else {
    digitalWrite(ledGreen, HIGH);
  }
}