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):
    # Check if "AB" and "BA" exist in the string, non-overlapping
    index_AB = s.find("AB")
    if index_AB != -1 and s.find("BA", index_AB + 2) != -1 and s.find("BA", index_AB + 2) != index_AB + 1:
        return "YES"

    index_BA = s.find("BA")
    if index_BA != -1 and s.find("AB", index_BA + 2) != -1 and s.find("AB", index_BA + 2) != index_BA + 1:
        return "YES"

    return "NO"

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