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.

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Example 1:

Input: time = "?5:00"Output: 2Explanation: 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: 100Explanation: Each ? can be replaced by any digit from 0 to 9, so we have 100 total choices.

Example 3:

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

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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.

• 難度等級：Easy
  

只要知道小時的可能性跟分鐘的可能是單獨(dú)即可，

先去判斷小時的可能性，如果2個都是？，是多少個，如果第1個是？，多少個，如果第2個是？，多少個，同理判斷分鐘的可能性；

最后返回小時跟分鐘可能性的乘積即可。

Runtime0 ms

Beats

100%

Memory39.8 MB

Beats

94.41%

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