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: Wrong Answer)

import java.util.*
import java.math.*
fun main(args: Array<String>) {

//    var (N, K) = readLine()!!.split(" ").map { it.toInt() }
    var N = readLine()!!.toInt()
//    val D = readLine()!!.split(" ").map { it.toLong() }
//    val A = readLine()!!.split(" ").map { it.toInt() }.toIntArray()

    var ans=0
    var A = 0
    var B = 0
    var sep = false
    //ABA BA BA BA
    for (i in 0 until N) {
        val S = readLine()!!
        if (S.last() == 'A') A++
        if (S.first() == 'B') B++
        if (!sep && A != B) sep = true

        var isA = false
        for (c in S) {
            if (isA && c == 'B') ans++
            isA = c == 'A'
        }
    }
    var min = Math.min(A,B)
    if (!sep) min--
    println(ans+min)
}