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 Python (3.4.3) (judge verdict: Wrong Answer)

# encoding:utf-8
import copy
import random
import bisect #bisect_left　これで二部探索の大小検索が行える
import fractions #最小公倍数などはこっち
import math

mod = 10**9+7

N = int(input())
s = [0 for i in range(N)]
cnt = 0
chance = False
A_cnt = 0
B_cnt = 0
BA_cnt = 0
for i in range(N):
    s[i] = str(input())
    cnt += s[i].count("AB")
    if s[i][0] == "B" and s[i][-1]=="A":
        BA_cnt += 1
    elif s[i][0] == "B":
        B_cnt += 1
    elif s[i][-1] == "A":
        A_cnt += 1


if BA_cnt != 0 and A_cnt == 0:
    plus = BA_cnt-1
else:
    plus = min(BA_cnt+A_cnt,BA_cnt+B_cnt)

cnt += plus

print(cnt)