HERDING  Herding
Oh no! A number of stray cats have been let loose in the city, and as the City Cat Catcher, you have been assigned the vital task of retrieving all of the cats. This is an ideal opportunity to test your latest invention, a cat trap which is guaranteed to retrieve every cat which walks into a squareshaped subsection of the city.
Fortunately, you have the assistance of one of the world's foremost cat psychologists, who has the amazing ability of predicting, given a square subsection of the city, exactly which of the four cardinal directions (north, east, south or west) the cat will head. While this information is handy, you still don't know where all the cats currently are.
In order to prove the costeffectiveness of your method to the City it would, of course, be important to minimize the number of traps used.
Input
The input will begin with a line consisting of two numbers n and m, separated by a space (1 ≤ n, m ≤ 1000). The city will be an n x m grid of square subsections. The next n lines will each consist of a string of length m, consisting of the letters 'N', 'E', 'S', or 'W', representing north, east, south and west, respectively. (The first character of the first line will be the northwesternmost point.) The direction in the square is the direction which cats will head if they are in that square. The cat psychologist assures you that cats have no interest in leaving the city.
Output
Output the minimum number of traps needed.
Example
Input: 3 4 SWWW SEWN EEEN Output: 2
hide comments
Chirag Gupta:
20140113 19:30:30
used scanf instead of getline and got AC..!!


LeppyR64:
20130903 16:31:13
The input format is correct. Akhilesh has not considered that there a multiple types of EOL. This problem has CRLF at the end of line. Not just LF. 

Akhilesh Anandh:
20130831 15:34:30
Bad input format. Got WA with getchar(); accepted with scanf("%s").


mala da.... annamala:
20130715 10:36:03
Simple logic is enough.... 

nagato:
20130619 19:34:45
easy one ...:) 

ankit agarwal:
20130428 05:21:30
sudipto das


Shubhdeep:
20121223 20:16:02
Nice problem :)) Last edit: 20121223 20:20:37 

gourav:
20121215 09:21:57
my new friend: spoj.. luv you spoj :) learning alot from you.. thank you Last edit: 20121215 09:27:11 

P$ycH0c0d(R:
20121202 07:23:12
what if both n=1,m=1..??? 
Added by:  JaceTheMindSculptor 
Date:  20090407 
Time limit:  0.902s1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: C99 ERL JSRHINO 
Resource:  Canadian Computing Competition 2008 Stage 2 Day 2 Problem D 