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### by Sumit Chourasia | Jan 26, 2021 | Category :coding | Tags : algorithmdata-structureeasyleetcodestring #### Latest Time by Replacing Hidden Digits - String - Easy - LeetCode

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.

``````public class Solution {
public string MaximumTime(string time) {
var times = time.ToCharArray();
if(times == '?') {
times = times <= '3' || times == '?' ? '2' : '1';
}

if(times == '?') {
times = times == '2' ? '3' : '9';
}

if(times == '?') {
times = '5';
}

if(times == '?') {
times = '9';
}

return new String(times);
}
}``````

Time Complexity: O(1)

Space Complexity: O(1)