3114. Latest Time You Can Obtain After Replacing Characters

Problem Link

Description

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You are given a string s representing a 12-hour format time where some of the digits (possibly none) are replaced with a "?".

12-hour times are formatted as "HH:MM", where HH is between 00 and 11, and MM is between 00 and 59. The earliest 12-hour time is 00:00, and the latest is 11:59.

You have to replace all the "?" characters in s with digits such that the time we obtain by the resulting string is a valid 12-hour format time and is the latest possible.

Return the resulting string.

 

Example 1:

Input: s = "1?:?4"

Output: "11:54"

Explanation: The latest 12-hour format time we can achieve by replacing "?" characters is "11:54".

Example 2:

Input: s = "0?:5?"

Output: "09:59"

Explanation: The latest 12-hour format time we can achieve by replacing "?" characters is "09:59".

 

Constraints:

• s.length == 5
• s[2] is equal to the character ":".
• All characters except s[2] are digits or "?" characters.
• The input is generated such that there is at least one time between "00:00" and "11:59" that you can obtain after replacing the "?" characters.

Solution

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Python3

class Solution:
    def findLatestTime(self, s: str) -> str:
        s = list(s)
        
        if s[0] == "?":
            if "2" <= s[1] <= "9":
                s[0] = "0"
            else:
                s[0] = "1"
        
        if s[1] == "?":
            if s[0] == "0":
                s[1] = "9"
            else:
                s[1] = "1"
        
        if s[3] == "?":
            s[3] = "5"
        
        if s[4] == "?":
            s[4] = "9"
        
        return "".join(s)