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).
The only line of input contains a string *s* of length between 1 and 10<sup class="upper-index">5</sup> consisting of uppercase Latin letters.
def check_substrings(s):
    first_occurrence = s.find("AB")  # Find the first occurrence of "AB"
    if first_occurrence != -1:
        second_occurrence = s.find("BA", first_occurrence + 2)  # Find "BA" after the first occurrence of "AB"
        if second_occurrence != -1:
            return "YES"  # Both substrings "AB" and "BA" are found

    return "NO"  # Substrings not found or order is incorrect


# Example usage
s = input()
result = check_substrings(s)
print(result)
