Problem:
Score : 400 points

Problem Statement

Snuke has N strings. The i-th string is s_i.

Let us concatenate these strings into one string after arranging them in some order.
Find the maximum possible number of occurrences of AB in the resulting string.

Constraints

1 \leq N \leq 10^{4}

2 \leq |s_i| \leq 10

s_i consists of uppercase English letters.

Input

Input is given from Standard Input in the following format:

N
s_1
\vdots
s_N

Output

Print the answer.

Sample Input 1

3
ABCA
XBAZ
BAD

Sample Output 1

2

For example, if we concatenate ABCA, BAD and XBAZ in this order, the resulting string ABCABADXBAZ has two occurrences of AB.

Sample Input 2

9
BEWPVCRWH
ZZNQYIJX
BAVREA
PA
HJMYITEOX
BCJHMRMNK
BP
QVFABZ
PRGKSPUNA

Sample Output 2

4

Sample Input 3

7
RABYBBE
JOZ
BMHQUVA
BPA
ISU
MCMABAOBHZ
SZMEHMA

Sample Output 3

4

Solution in Haskell (GHC 7.10.3) (judge verdict: Wrong Answer)

import           Control.Monad (replicateM)
import           Data.List     (isInfixOf)

main :: IO ()
main = do
  n <- readLn
  ss <- replicateM n getLine
  print $ solve ss

solve :: [String] -> Int
solve ss =
  let
    containAB = length $ filter ("AB" `isInfixOf`) ss
    endWithA = length $ filter ((== 'A') . last) ss
    startWithB = length $ filter ((== 'B') . head) ss
    startWithBAndEndWithA = length $ filter ((== 'A') . last) $ filter ((== 'B') . head) ss
    startWithoutBAndEndWithA = endWithA - startWithBAndEndWithA
    startWithBAndEndWithoutA = startWithB - startWithBAndEndWithA
  in
    containAB + startWithBAndEndWithA + min startWithoutBAndEndWithA startWithBAndEndWithoutA