public String decode(String k) {

        StringBuilder input1 = new StringBuilder();
        input1.append(k);
        input1 = input1.reverse();
        char[] charA = input1.toString().toCharArray();
        int[] numericVect = new int[charA.length];
        StringBuilder result = new StringBuilder();

        for (int i = 0; i < charA.length; i++) {
            numericVect[i] = Character.getNumericValue(charA[i]);
        }

        int i = 0;
        int number = 0;
        while (i < charA.length){
            number = numericVect[i] * 10 + numericVect[i+1];

            if (number == 32) {
                result.append((char) number);
                i += 2;
                continue;
            }

            if ((number >= 65 && number <= 95) || (number >= 97 && number < 100)) {
                result.append((char)number);
                i += 2;
                continue;
            }

            number = numericVect[i] * 100 + numericVect[i+1] * 10 + numericVect[i+2];
            result.append((char)number);
            i += 3;

        }

        return  result.toString();
    }