Handling multiple ultrasonic sensors with Arduino!

1//Our library
2#include <Ultrasonic.h>
3
4//Define led pins 
5#define led1 9
6#define led2 8
7#define led3 7
8
9//Create "ultrasonic" objects
10Ultrasonic ultrasonic1(13, 12);
11Ultrasonic ultrasonic2(13, 11);
12Ultrasonic ultrasonic3(13, 10);
13
14//Integers to store sensor readings
15int val1;
16int val2;
17int val3;
18
19void setup() {
20  //Start serial at 9600 baud rate
21  Serial.begin(9600);
22
23  //Leds as output (leds are debuggers)
24  pinMode(led1, OUTPUT);
25  pinMode(led2, OUTPUT);
26  pinMode(led3, OUTPUT);
27}
28
29void loop() {
30  //Ping sequence
31  //The library read values in centimeters, by default
32  val1 = ultrasonic1.read();  //Reads sensor 1
33  delay(50);                  //Small delay between readings
34  val2 = ultrasonic2.read();  //Read sensor 2
35  delay(50);
36  val3 = ultrasonic3.read();  //Read sensor 3
37  delay(50);
38
39  //Print on serial monitor
40  Serial.print(val1);
41  Serial.print("  |  ");
42  Serial.print(val2);
43  Serial.print("  |  ");
44  Serial.println(val3);
45
46  //LED debug
47  //If close enough from sensor 1
48  if (val1 < 20) {
49    digitalWrite(led1, HIGH);
50  } else {
51    digitalWrite(led1, LOW);
52  }
53   //If close enough from sensor 2
54  if (val2 < 20) {
55    digitalWrite(led2, HIGH);
56  } else {
57    digitalWrite(led2, LOW);
58  }
59   //If close enough from sensor 3
60  if (val3 < 20) {
61    digitalWrite(led3, HIGH);
62  } else {
63    digitalWrite(led3, LOW);
64  }
65}