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#F1650. Two Substrings

    ID: 1656 传统题 2000ms 256MiB 尝试: 0 已通过: 0 难度: 4 上传者: 标签>枚举动态规划贪心模拟字符串算法思想编程与模拟进阶难度共享题库Codeforces英文题面题目来源题面语言

Two Substrings

题目描述

A. Two Substrings
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

You are given string s. Your task is to determine if the given string s contains two non-overlapping substrings "AB" and "BA" (the substrings can go in any order).

Input

The only line of input contains a string s of length between 1 and 105 consisting of uppercase Latin letters.

Output

Print "YES" (without the quotes), if string s contains two non-overlapping substrings "AB" and "BA", and "NO" otherwise.

Examples
Input
ABA
Output
NO
Input
BACFAB
Output
YES
Input
AXBYBXA
Output
NO
Note

In the first sample test, despite the fact that there are substrings "AB" and "BA", their occurrences overlap, so the answer is "NO".

In the second sample test there are the following occurrences of the substrings: BACFAB.

In the third sample test there is no substring "AB" nor substring "BA".

题目来源：fps-www.educg.net-codeforce-1-2833.xml.zip；FPS 共享题包，题包内第 1179 题。保留原作者与原赛事署名。