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)

n = int(input())
S = []
for i in range(n):
    s = str(input())
    S.append(s)
    
ans = 0
countA = 0
countB = 0
countBA = 0
for s in S:
    if s[0] == 'B' and s[len(s)-1] == 'A':
        countBA += 1
        
    elif s[len(s)-1] == 'A':
        countA += 1
        
    if s[0] == 'B':
        countB += 1
        
    for i in range(len(s) - 1):
        if s[i] == 'A' and s[i+1] == 'B':
            ans += 1
            
            
if countA > countB:
    ans += countB
    countA -= countB
    
    if countA > countBA:
        ans += countBA
        
    else:
        ans += countA
        countBA -= countA
        ans += countBA // 2
        if countBA // 2 >= 1:
            ans += 1
        
else:
    ans += countA
    countB -= countA
    
    if countB > countBA:
        ans += countBA
        
    else:
        ans += countB
        countBA -= countB
        ans += countBA // 2 
        if countBA // 2 >= 1:
            ans += 1
        
print(ans)