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 Go (1.6) (judge verdict: Wrong Answer)

package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func getNextLine(scanner *bufio.Reader) string {
	var buffer string
	for {
		line, isPrefix, _ := scanner.ReadLine()
		buffer += string(line)
		if isPrefix == false {
			break
		}
	}
	return buffer
}

func getIntList(scanner *bufio.Reader) []int {
	list := strings.Split(getNextLine(scanner), " ")
	l := len(list)
	result := make([]int, l)
	for i := 0; i < l; i++ {
		result[i], _ = strconv.Atoi(list[i])
	}
	return result
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := bufio.NewReader(fp)

	var n int

	fmt.Sscan(getNextLine(scanner), &n)
	bstart := 0
	aend := 0
	both := 0
	ans := 0
	for i := 0; i < n; i++ {
		s := getNextLine(scanner)
		if s[0] == 'B' {
			bstart++
		}
		if s[len(s)-1] == 'A' {
			aend++
		}
		if s[0] == 'B' && s[len(s)-1] == 'A' {
			both++
		}
		for j := 1; j < len(s); j++ {
			if s[j-1] == 'A' && s[j] == 'B' {
				ans++
			}
		}
	}
	ans += minint(minint(bstart, aend), n-1)
	if bstart == aend && bstart == both && n > both {
		ans--
	}
	fmt.Println(ans)
}
func minint(a int, b int) int {
	if a < b {
		return a
	}
	return b
}