1736

1736. Latest Time by Replacing Hidden Digits (Easy)

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.

Related Topics:
String, Greedy

Solution 1.

// OJ: https://leetcode.com/problems/latest-time-by-replacing-hidden-digits/
// Author: github.com/lzl124631x
// Time: O(1)
// Space: O(1)
class Solution {
public:
    string maximumTime(string time) {
        if (time[0] == '?') time[0] = time[1] == '?' || time[1] <= '3' ? '2' : '1';
        if (time[1] == '?') time[1] = time[0] == '2' ? '3' : '9';
        if (time[3] == '?') time[3] = '5';
        if (time[4] == '?') time[4] = '9';
        return time;
    }
};