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"
)

var sc = bufio.NewScanner(os.Stdin)

func nextLine() string {
	sc.Scan()
	return sc.Text()
}

func allAtoi(num []string) []int {
	conv := make([]int, len(num))
	for i, item := range num {
		conv[i], _ = strconv.Atoi(item)
	}
	return conv
}

func main() {
	n, _ := strconv.Atoi(nextLine())
	abCnt := 0
	tailACnt := 0
	headBCnt := 0
	for i := 0; i < n; i++ {
		str := nextLine()
		cnt := strings.Count(str, "AB")
		abCnt += cnt
		if strings.HasPrefix(str, "B") {
			headBCnt++
		}
		if strings.HasSuffix(str, "A") {
			tailACnt++
		}
	}
	var min int
	if tailACnt < headBCnt {
		min = tailACnt
	} else {
		min = headBCnt
	}
	ans := min + abCnt
	fmt.Println(ans)
}