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.
s = input()

# Check if "AB" and "BA" exist in the string
if "AB" in s and "BA" in s:
    # Find the indices of the first occurrence of "AB" and "BA"
    ab_index = s.index("AB")
    ba_index = s.index("BA")

    # Check if the absolute difference between the indices is at least 2
    if abs(ab_index - ba_index) > 1:
        print("YES")
    else:
        print("NO")
else:
    print("NO")
