Clone PS2X library with Cute Function isCloseTo

//"ชอบรูปแบบการเขียนฟังก์ชั่น isCloseTo() จึงขอเก็บบันทึกเอาไว้"
#include <PS2X_lib.h>  //for v1.6

PS2X ps2x; // create PS2 Controller Class
int ly, lx, ry, rx;

//right now, the library does NOT support hot pluggable controllers, meaning
//you must always either restart your Arduino after you conect the controller,
//or call config_gamepad(pins) again after connecting the controller.
int error = 0;
byte type = 0;
byte vibrate = 0;
int lastReadings[] = {0, 0, 0, 0};

void setup(){
 Serial.begin(9600);

 error = ps2x.config_gamepad(9,11,10,12, true, true);
 //setup pins and settings:  GamePad(clock, command, attention, data, Pressures?, Rumble?) check for error

 if(error == 0){
   Serial.println("Found Controller, configured successful");
   Serial.println("Try out all the buttons, X will vibrate the controller, faster as you press harder;");
  Serial.println("holding L1 or R1 will print out the analog stick values.");
  Serial.println("Go to www.billporter.info for updates and to report bugs.");
 }
}

void loop(){
 if(error == 1) //skip loop if no controller found
  return;

  ps2x.read_gamepad(false, vibrate);          //read controller and set large motor to spin at 'vibrate' speed

  // Update joystick values
  ly = ps2x.Analog(PSS_LY);
  lx = ps2x.Analog(PSS_LX);
  ry = ps2x.Analog(PSS_RY);
  rx = ps2x.Analog(PSS_RX);

  // If joystick values are reasonably close together (not too far from the last reading, as they would be if they were outliers,
  // print out the values (effectively filtering out outliers)
  if(isCloseTo(ly, lastReadings[0]) &&
    isCloseTo(lx, lastReadings[1]) &&
    isCloseTo(ry, lastReadings[2]) &&
    isCloseTo(rx, lastReadings[3])) {
    Serial.print("Stick Values:");
    Serial.print(ly, DEC); //Left stick, Y axis. Other options: LX, RY, RX
    Serial.print(",");
    Serial.print(lx, DEC);
    Serial.print(",");
    Serial.print(ry, DEC);
    Serial.print(",");
    Serial.println(rx, DEC);
  }

  // Populate our array with the last set of readings
  lastReadings[0] = ly;
  lastReadings[1] = lx;
  lastReadings[2] = ry;
  lastReadings[3] = rx;

  delay(10);
}

// Determines if two numbers are close together; returns true if they are, returns false if they're too far apart (difference in readings >= 50)
boolean isCloseTo(int x, int y) {
  return abs(x - y) < 50;
}