char input;
String in = "";
const int ledPin = 13;

void setup() {
  Serial.begin(9600);
  Serial.setTimeout(10);
  pinMode(ledPin,OUTPUT);
}
void loop() {
  while (Serial.available()==0){}
  while (Serial.available() > 0){
    input = Serial.read();
    Serial.println("The value of n " + String(input));
    in.concat(input);
    if (isPalindrome(in)){
      digitalWrite(ledPin,HIGH);
      Serial.println("Now Input is " + in);
      Serial.println("Is Palimdrome Led Is ON");
    }
    else{
      digitalWrite(ledPin,LOW);
      Serial.println("Now Input is " + in);
      Serial.println("Is Not Palimdrome Led Is OFF");
    }
  }
  Serial.println("Final Input is " + in);
}

boolean isPalindrome(String original){
       String reverse = ""; // Objects of String class
      int length = original.length();
      for ( int i = length - 1; i >= 0; i-- )
         reverse = reverse + original.charAt(i);
      if (original.equals(reverse))
         return true;
      else
         return false;
}