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 Kotlin (1.0.0) (judge verdict: Accepted)

fun main(args: Array<String>) {
    val N=readLine()!!.toInt()
    val s =Array(N){ readLine()!! }
    var ab=0
    var a=0
    var b=0
    var ba=0
    s.forEach {
        it.forEachIndexed { i,c1->if(i<it.length-1&&c1=='A'&&it[i+1]=='B')ab+=1 }
        if(it[0]=='B'){
            if(it[it.length-1]=='A')ba+=1
            else b+=1
        }else if(it[it.length-1]=='A')a+=1
    }
    var abab=Math.min(ba,Math.min(a,b))
    ba-=abab
    a-=abab
    b-=abab
    var tba=0
    if(ba>0){
        if(abab>0)tba=ba
        else {
            tba=ba-1
            if(Math.max(a,b)>0)tba+=1
        }
    }else{
        tba=Math.min(a,b)
    }
    print(ab+abab*2+tba)
}