1736. Latest Time by Replacing Hidden Digits-替换隐藏数字得到的最晚时间

You are given a string time in the form of hh:mm, where some of the digits in the string are hidden (represented by ?).

The valid times are those inclusively between 00:00 and 23:59.

Return the latest valid time you can get from time by replacing the hidden digits.

Example 1:
Input: time = "2?:?0"
Output: "23:50"
Explanation: The latest hour beginning with the digit ‘2’ is 23 and the latest minute ending with the digit ‘0’ is 50.

Example 2:
Input: time = "0?:3?"
Output: "09:39"

Example 3:
Input: time = "1?:22"
Output: "19:22"

Constraints:

• time is in the format hh:mm.
• It is guaranteed that you can produce a valid time from the given string.

Solution in python:

class Solution:
    def maximumTime(self, time: str) -> str:
        alist = list(time)
        if alist[3] == '?':
            alist[3] = '5'
        if alist[4] == '?':
            alist[4] = '9'
        if alist[0] == '?' and alist[1] == '?':
            alist[0] = '2'
            alist[1] = '3'
        elif alist[0] == '?' and alist[1] > '3':
            alist[0] = '1' 
        elif alist[0] == '?' and alist[1] <= '3':
            alist[0] = '2'
        elif alist[0] > '1' and alist[1] == '?':
            alist[1] = '3'
        elif alist[0] <= '1' and alist[1] == '?':
            alist[1] = '9'
        return ''.join(alist)