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()!!}
    val a=s.indices.filter{s[it].last()=='A'}
    val b=s.indices.filter{s[it].first()=='B'}
    val ab=s.indices.filter{s[it].first()=='B'&&s[it].last()=='A'}
    var ans=0
    for(t in s){
        for(i in 0..t.length-2) {
            ans += if (t.slice(i..i + 1) == "AB") 1 else 0
        }
    }
    if(ab==a&&ab==b&&ab.size>0){
        println(ans+Math.min(a.size,b.size)-1)
    }
    else{
        println(ans+Math.min(a.size,b.size))
    }
}