class Solution:
    def plusOne(self, digits: List[int]) -> List[int]:

        z = len(digits) - 1
        carry = 1

        while (z>=0 and carry>0):
            carry = (digits[z] + 1)//10
            digits[z] = (digits[z] + 1)%10
            z = z - 1

        if carry > 0:
            digits = [1] + digits

        return digits