You are given a?0-indexed?integer array?forts?of length?n?representing the positions of several forts.?forts[i]?can be?-1,?0, or?1?where:

• -1?represents there is?no fort?at the?ith?position.

• 0?indicates there is an?enemy?fort at the?ith?position.

• 1?indicates the fort at the?ith?the position is under your command.

Now you have decided to move your army from one of your forts at position?i?to an empty position?j?such that:

• 0 <= i, j <= n - 1

• The army travels over enemy forts?only. Formally, for all?k?where?min(i,j) < k < max(i,j),?forts[k] == 0.

While moving the army, all the enemy forts that come in the way are?captured.

Return?the?maximum?number of enemy forts that can be captured. In case it is?impossible?to move your army, or you do not have any fort under your command, return?0.

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Example 1:

Input: forts = [1,0,0,-1,0,0,0,0,1]Output: 4Explanation:- Moving the army from position 0 to position 3 captures 2 enemy forts, at 1 and 2. - Moving the army from position 8 to position 3 captures 4 enemy forts. Since 4 is the maximum number of enemy forts that can be captured, we return 4.

Example 2:

Input: forts = [0,0,1,-1]Output: 0Explanation: Since no enemy fort can be captured, 0 is returned.

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Constraints:

• 1 <= forts.length <= 1000

• -1 <= forts[i] <= 1

Easy題目，不贅述；

Runtime0 ms

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Memory39.7 MB

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