NO.1

public static String balik(String s){
        String kata = "";
        String [] pisah = s.split("");
        int pjg = s.length();
        int bts = pjg/2;
        for(int i = 0; i < bts; i++,pjg--){
            String smp = pisah[i];
            pisah[i] = pisah[pjg-1];
            pisah[pjg-1] = smp;
        }

        String hasil = "";
        for(int i = 0; i < s.length(); i++){
            hasil = hasil + pisah[i];
        }
        return hasil;
    }
    public static void main(String[] args) {
        Scanner masuk = new Scanner (System.in);
        String kata = masuk.nextLine();
        String hasil = balik(kata);
        String []angka = hasil.split(" ");
        int A = Integer.parseInt(angka[0]);
        int B = Integer.parseInt(angka[1]);
        A = A + B;
        kata = Integer.toString(A);
        hasil = balik(kata);
        A = Integer.parseInt(hasil);
        System.out.println(A);
    }