#P4691. Two Substrings
Two Substrings
Two Substrings
题面翻译
给你一个字符串 (),判断 中是否有不相交的 , 这两个子串。如果存在,输出 Yes
,否则输出 No
。
题目描述
You are given string . Your task is to determine if the given string contains two non-overlapping substrings "AB" and "BA" (the substrings can go in any order).
输入格式
The only line of input contains a string of length between and consisting of uppercase Latin letters.
输出格式
Print "YES" (without the quotes), if string contains two non-overlapping substrings "AB" and "BA", and "NO" otherwise.
样例 #1
样例输入 #1
ABA
样例输出 #1
NO
样例 #2
样例输入 #2
BACFAB
样例输出 #2
YES
样例 #3
样例输入 #3
AXBYBXA
样例输出 #3
NO
提示
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".