#define TRIG_PIN_2 7 // Trig pin definition for ultrasound sensor 2
#define ECHO_PIN_2 0 // Echo pin definition for ultrasound sensor 2
#define TRIG_PIN_3 2 // Trig pin definition for ultrasound sensor 3
#define ECHO_PIN_3 1 // Echo pin definition for ultrasound sensor 3
#define TRIG_PIN_1 29 // Trig pin definition for ultrasound sensor 1
#define ECHO_PIN_1 6 // Echo pin definition for ultrasound sensor 1

void setup() {
  Serial.begin(9600);           // Initialize serial communication at 9600 baud
  pinMode(TRIG_PIN_1, OUTPUT);  // Set sensor 1 trig pin as output
  pinMode(ECHO_PIN_1, INPUT);   // Set sensor 1 echo pin as input
  pinMode(TRIG_PIN_2, OUTPUT);  // Set sensor 2 trig pin as output
  pinMode(ECHO_PIN_2, INPUT);   // Set sensor 2 echo pin as input
  pinMode(TRIG_PIN_3, OUTPUT);  // Set sensor 3 trig pin as output
  pinMode(ECHO_PIN_3, INPUT);   // Set sensor 3 echo pin as input
}

void loop() {
  // Read the first ultrasound sensor
  long duration_1, distance_1;
  digitalWrite(TRIG_PIN_1, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN_1, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN_1, LOW);
  duration_1 = pulseIn(ECHO_PIN_1, HIGH);
  distance_1 = duration_1 * 0.034 / 2;

  // Read the second ultrasound sensor
  long duration_2, distance_2;
  digitalWrite(TRIG_PIN_2, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN_2, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN_2, LOW);
  duration_2 = pulseIn(ECHO_PIN_2, HIGH);
  distance_2 = duration_2 * 0.034 / 2;

  // Read the third ultrasound sensor
  long duration_3, distance_3;
  digitalWrite(TRIG_PIN_3, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN_3, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN_3, LOW);
  duration_3 = pulseIn(ECHO_PIN_3, HIGH);
  distance_3 = duration_3 * 0.034 / 2;

  // Print the distances measured on the serial port
  Serial.print("Sensor distance 1: ");
  Serial.print(distance_1);
  Serial.println(" cm");
  Serial.print("Sensor distance 2: ");
  Serial.print(distance_2);
  Serial.println(" cm");
  Serial.print("Sensor distancer 3: ");
  Serial.print(distance_3);
  Serial.println(" cm");

  // Wait 1 second before taking another reading
  delay(1000);
}