import java.util.*;
import java.io.*;
public class NumberFilter {
    //public static void main(String[] args){
    public void filter(String str){


        PrintWriter outputStream =null;
        try{
        outputStream = new PrintWriter(new FileOutputStream(str));
    }
        catch(FileNotFoundException e){
            System.out.println("Error creating the file");
            System.exit(0);
        }
        String input;
        int pairs =0;

        while(true){
        Scanner scan = new Scanner(System.in);
        System.out.println("Enter a String!");
        input = scan.nextLine();


        if (input.equalsIgnoreCase("quit")) break;

        //if (input.contains("aa") || input.contains("bb") || input.contains("cc") || input.contains("dd")){
          //  System.out.println("Dont enter two or more consective numbers");
            //input = scan.nextLine();
        //}

        for (int i = 0; i < input.length()-1; i++) {
            //alpha.length()-1 so you won't get an ArrayOutOfBoundsException
            //in the if statement at the next line. i++ to stop the loop being
            //infinite.
            if (input.charAt(i) == input.charAt(i + 1)) {
                pairs++;
                                System.out.println("Dont enter two consective numbers or letters!");
                                input  = scan.nextLine();
                        }


        }

            outputStream.println(input);
        }

            outputStream.close();

    }
}