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):
    found_AB = False
    found_BA = False

    for i in range(len(s) - 1):
        if s[i:i + 2] == "AB" and not found_AB:
            found_AB = True
        elif s[i:i + 2] == "BA" and not found_BA:
            found_BA = True

        if found_AB and found_BA:
            return "YES"

    return "NO"

# Example usage
s = input("Enter the string: ")
result = check_substrings(s)
print(result)
