2782.Two Substrings

Time Limit: 1s Memory Limit: 256MB

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 Format(From the terminal/stdin)

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

Output Format(To the terminal/stdout)

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

Sample Input 1

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ABA
   \n

Sample Output 1

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NO
  \n

Sample Input 2

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BACFAB
      \n

Sample Output 2

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YES
   \n

Sample Input 3

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AXBYBXA
       \n

Sample Output 3

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NO
  \n

Hints

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".

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