leetcode 2086. Minimum Number of Food Buckets to Feed the Hamste

You are given a 0-indexed string hamsters where hamsters[i] is either:

• 'H' indicating that there is a hamster at index i, or

• '.' indicating that index i is empty.

You will add some number of food buckets at the empty indices in order to feed the hamsters. A hamster can be fed if there is at least one food bucket to its left or to its right. More formally, a hamster at index i can be fed if you place a food bucket at index i - 1 and/or at index i + 1.

Return the minimum number of food buckets you should place at empty indices to feed all the hamsters or -1 if it is impossible to feed all of them.

Example 1:

Input: hamsters = "H..H"Output: 2Explanation: We place two food buckets at indices 1 and 2. It can be shown that if we place only one food bucket, one of the hamsters will not be fed.

Example 2:

Input: hamsters = ".H.H."Output: 1Explanation: We place one food bucket at index 2.

Example 3:

Input: hamsters = ".HHH."Output: -1Explanation: If we place a food bucket at every empty index as shown, the hamster at index 2 will not be able to eat.

Constraints:

• 1 <= hamsters.length <= 105

• hamsters[i] is either'H' or '.'.

1：考虑边界条件；

2：先将H中间有.的清出来，然后，再去遍历剩下的H即可。

就是有点花时间了；

Runtime27 ms

Beats

10.8%

Memory50.4 MB

Beats

34.88%

这速度也是没谁了，慢的快不及格了。。。