#include <Ultrasonic.h>

#define TRIGGER_PIN1  12
#define ECHO_PIN1     13
#define TRIGGER_PIN2  10
#define ECHO_PIN2     11

Ultrasonic ultrasonic1(TRIGGER_PIN1, ECHO_PIN1);
Ultrasonic ultrasonic2(TRIGGER_PIN2, ECHO_PIN2);

void setup()
  {
  Serial.begin(9600);
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  }

void loop()
  {
  float cmMsec1, cmMsec2;
  long microsec1 = ultrasonic1.timing();
  long microsec2 = ultrasonic2.timing();
  cmMsec1 = ultrasonic1.convert(microsec1, Ultrasonic::CM);
  cmMsec2 = ultrasonic2.convert(microsec2, Ultrasonic::CM);
  Serial.print(cmMsec1);
  Serial.print(" ; ");
  Serial.println(cmMsec2);

 if (2<cmMsec1 && cmMsec1<4){
    Serial.println("Detected1");
    digitalWrite(2, 1);
    digitalWrite(3, 0);
  }
    else{
     digitalWrite(2, 0);
  }

  if (2<cmMsec2 && cmMsec2<4){
    Serial.println("Detected2");
    digitalWrite(3, 1);
    digitalWrite(2, 0);
  }
  else{
     digitalWrite(3, 0);
  }
  delay(50);
  }