public static String zamiana(String g) {

        String y = new String();
        int i=0;
        char zn=g.charAt(i);
        for ( i = 0; i < g.length(); i++) {

            if (zn >= 'A' && zn <= 'Z') {
                //zn=Character.toUpperCase(zn);
                zn = (char)(zn - 'A' + 'a');

            }
            if(zn>='a' && zn<='z'){
                zn=(char)(zn-'a'+'A');}

                        y+=zn;


        }

        return y;
    }


    public static void main(String[] args) {
      Scanner in=new Scanner(System.in);
      System.out.println("podaj ciag znakow");
        String x = new String();
        x = in.nextLine();
        System.out.print(zamiana(x));

    }