Lexio Swap

#https://www.codechef.com/problems/LEX

def getBlock(strn):
    last = ''
    block = []
    '''
    you are treating As and Bs as blocks
    so if the s string is homogenous(contains A and B) you can make those blocks into smallest blocks if required as per the given operations
    - even blocks can be made as small as 2 chars
    - odd blocks can be made as small as 1 char
    so this raises some simple conditions to check that s can be made as t or not
    those are
     - blocks orders should be matching for both sblock and tblock
     - parity of those blocks should be matching
     - sblock should be higher or equal to t block as sblock can be shrinked if required
    '''
    for ch in strn:
        if last==ch:
            block[-1][1]+=1
        else:
            last=ch
            block.append([ch,1])
    return block

def checkBlockOrdersAndVerify(sblock,tblock):
    #we reach this point only when both block lengths matches
    for index in range(len(sblock)):
        if sblock[index][0] != tblock[index][0]:#order validation
            return False
        if (sblock[index][1]%2) != (tblock[index][1]%2) :#parity validation
            return False
        if (sblock[index][1]) < (tblock[index][1]) :#length validation
            return False
    return True

def checkIfPossibleToMakeT(s,t):
    if 'A' not in s or 'A' not in t or 'B' not in s or 'B' not in t:
        #A or B is not present in one string ,so they have to match definitely to print YES
        if s==t:
            print('YES')
        else:
            print('NO')
        return
    sblock = getBlock(s)
    tblock = getBlock(t)
    if len(sblock)!=len(tblock):
        print('NO')
        return
    else:

        if(not checkBlockOrdersAndVerify(sblock,tblock)):
            print('NO')
            return
        else:
            print('YES')
            return



Q = int(input())
for _ in range(Q):
    n,m = map(int,input().split())
    s = input()
    t = input()
    checkIfPossibleToMakeT(s,t)