2437. Number of Valid Clock Times
Easy
192
179

You are given a string of length `5` called `time`, representing the current time on a digital clock in the format `"hh:mm"`. The earliest possible time is `"00:00"` and the latest possible time is `"23:59"`.

In the string `time`, the digits represented by the `?` symbol are unknown, and must be replaced with a digit from `0` to `9`.

Return an integer `answer`, the number of valid clock times that can be created by replacing every `?` with a digit from `0` to `9`.

Example 1:

```Input: time = "?5:00"
Output: 2
Explanation: We can replace the ? with either a 0 or 1, producing "05:00" or "15:00". Note that we cannot replace it with a 2, since the time "25:00" is invalid. In total, we have two choices.
```

Example 2:

```Input: time = "0?:0?"
Output: 100
Explanation: Each ? can be replaced by any digit from 0 to 9, so we have 100 total choices.
```

Example 3:

```Input: time = "??:??"
Output: 1440
Explanation: There are 24 possible choices for the hours, and 60 possible choices for the minutes. In total, we have 24 * 60 = 1440 choices.
```

Constraints:

• `time` is a valid string of length `5` in the format `"hh:mm"`.
• `"00" <= hh <= "23"`
• `"00" <= mm <= "59"`
• Some of the digits might be replaced with `'?'` and need to be replaced with digits from `0` to `9`.
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