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 contains_AB_BA(s):
    # Initialize variables to check if "AB" and "BA" are found
    has_AB = False
    has_BA = False
    
    # Iterate through the string
    for i in range(len(s) - 1):
        # Check for "AB" and "BA" substrings
        if s[i:i+2] == "AB":
            has_AB = True
        elif s[i:i+2] == "BA":
            has_BA = True

    # Check if both substrings were found
    return has_AB and has_BA

# Input
s = input()

# Check if the string contains both "AB" and "BA" non-overlapping substrings
result = contains_AB_BA(s)

# Print the result
if result:
    print("YES")
else:
    print("NO")

 					  		 	 	 	   	   	