class Solution:
    def sequentialDigits(self, low: int, high: int) -> List[int]:

        ans_list = []
        digit_range = range(len(str(low)),len(str(high))+1)

        for dr in digit_range:
            for i in range(1,11-dr):
                d = [str(x) for x in range(i,i+dr)]
                s = "".join(d)
                no = int(s)
                if no>=low and no<=high:
                    ans_list.append(no)

        return ans_list