public IntegerOperator getIntegerOperator(String string) {
        char[] chars = string.toCharArray();

        for(char c : chars) {
            if(c == '+') return IntegerOperator.ADD;
            else if(c == '-') return IntegerOperator.SUBTRACT;
            else if(c == '*') return IntegerOperator.MULTIPLY;
            else if(c == '/') return IntegerOperator.DIVIDE;
        }

        return IntegerOperator.ADD;
    }