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 Lua (5.3.2) (judge verdict: Accepted)

local N = io.read("n", "l")
local inner = 0
local endsA = 0 -- but not starts w/ B
local startsB = 0 -- but not ends w/ A
local both = 0
for i=1, N do
    local s = io.read("l")
    local head = string.sub(s, 1, 1)
    local tail = string.sub(s, #s, #s)
    if head == 'B' and tail == 'A' then
        both = both + 1
    elseif head == 'B' then
        startsB = startsB + 1
    elseif tail == 'A' then
        endsA = endsA + 1
    end
    for _ in string.gmatch(s, "AB") do
        inner = inner + 1
    end
end
local ans = inner
if both > 0 then
    ans = ans + both - 1
    if endsA > 0 then
        ans = ans + 1
        endsA = endsA - 1
    end
    if startsB > 0 then
        ans = ans + 1
        startsB = startsB - 1
    end
end
ans = ans + math.min(endsA, startsB)
print(ans)