How many Jimmys can fit? In this simple but fun challenge, you were asked to determine if Jimmy would fall of their platform.  Jimmy has three body parts /, o, and \ arranged like this

/o\


Platforms are represented with -.  Jimmy will fall off their platform iff they have two or more body parts that are not directly above a platform.

Some examples:

   /o\
- -------


Jimmy will balance since all their body parts are above a -.

   /o\
    ------   ---


Jimmy will balanced since two body parts are above -s.

 /o\
-- ----  --


Jimmy will balance even though they are split between two platforms

  /o\
   -


Jimmy will not balanced since two body parts are not above a platform.



Your task is to write a program that takes a platform as a lengthed container containing only -s and s (e.g. a string) and outputs the number of Jimmys that can be placed on the platform such that none of them will fall and none of them will overlap.  A Jimmy may have one of their body parts to the left of the beginning of the string or the right of the end of the string.

This is code-golf so answers are scored in bytes with fewer bytes being the aim.

Test cases

Inputs

-  -  -

- -
--
-- --
----
- -- --
------- -


Respective outputs

0
0
1
1
2
2
2
3
JavaScript (ES6),  45 41  40 bytes
Saved 4 bytes thanks to @Shaggy

s=&gt;(0+s+0).split(/.--|-.-|--./).length-1

Try it online!