Buggy python submission (verdict: Runtime Error):
S = list(input())
T = list(input())

# S=list("BBAAABA")
# T=list("BBBA")

q = int(input())

l = []
for i in range(q):
	l.append(list(map(int,input().split(" "))))


sta = [0 for i in range(len(S))]
stb = [0 for i in range(len(S))]

tta = [0 for i in range(len(T))]
tta = [0 for i in range(len(T))]

if S[0] == "A":
	sta[0] = 1
else:
	stb[0] = 1

if T[0] == "A":
	tta[0] = 1
else:
	ttb[0] = 1

for i in range(1,len(S)):
	if S[i] == "A":
		sta[i] = sta[i-1]+1
	else:
		stb[i] = stb[i-1]+1

for i in range(1,len(T)):
	if T[i] == "A":
		tta[i] = tta[i-1]+1
	else:
		ttb[i] = ttb[i-1]+1

def get(l,a,b):
	if a == 0:
		return(l[b])
	else:
		return(l[b]-l[a-1])
		
for a,b,c,d in l:
	sa = get(sta,a-1,b-1)
	sb = get(stb,a-1,b-1)
	ta = get(tta,c-1,d-1)
	tb = get(ttb,c-1,d-1)


	if (sa+sb*2)%3 == (ta+tb*2)%3:
		print("YES")
	else:
		print("NO")





















Fixed submission:
S = list(input())
T = list(input())

# S=list("BBAAABA")
# T=list("BBBA")

q = int(input())

l = []
for i in range(q):
	l.append(list(map(int,input().split(" "))))


sta = [0 for i in range(len(S))]
stb = [0 for i in range(len(S))]

tta = [0 for i in range(len(T))]
ttb = [0 for i in range(len(T))]

if S[0] == "A":
	sta[0] = 1
else:
	stb[0] = 1

if T[0] == "A":
	tta[0] = 1
else:
	ttb[0] = 1

for i in range(1,len(S)):
	if S[i] == "A":
		sta[i] = sta[i-1]+1
		stb[i] = stb[i-1]
	else:
		sta[i] = sta[i-1]
		stb[i] = stb[i-1]+1

for i in range(1,len(T)):
	if T[i] == "A":
		tta[i] = tta[i-1]+1
		ttb[i] = ttb[i-1]
	else:
		tta[i] = tta[i-1]
		ttb[i] = ttb[i-1]+1


def get(l,a,b):
	if a == 0:
		return(l[b])
	else:
		return(l[b]-l[a-1])

for a,b,c,d in l:
	sa = get(sta,a-1,b-1)
	sb = get(stb,a-1,b-1)
	ta = get(tta,c-1,d-1)
	tb = get(ttb,c-1,d-1)


	if (sa+sb*2)%3 == (ta+tb*2)%3:
		print("YES")
	else:
		print("NO")

Buggy python submission (verdict: Time Limit Exceeded):
S = list(input())
T = list(input())

# S=list("BBAAABA")
# T=list("BBBA")

q = int(input())

l = []
for i in range(q):
	l.append(list(map(int,input().split(" "))))


i = 1
while i < len(S):
	i <<= 1
sta = [0 for i in range(i*2)]

i = 1
while i < len(S):
	i <<= 1
stb = [0 for i in range(i*2)]

i = 1
while i < len(T):
	i <<= 1
tta = [0 for i in range(i*2)]

i = 1
while i < len(T):
	i <<= 1
ttb = [0 for i in range(i*2)]

for i in range(len(S)):
	if S[i] == "A":
		sta[i+len(sta)//2] = 1
	else:
		stb[i+len(stb)//2] = 1

for i in range(len(T)):
	if T[i] == "A":
		tta[i+len(tta)//2] = 1
	else:
		ttb[i+len(ttb)//2] = 1

def make(l):
	def do(i):
		if i >= len(l)//2:
			return(l[i])
		else:
			l[i] = do(i*2)+do(i*2+1)
			return(l[i])

	do(1)

def get(li,a,b):   #[a,b]を調べる
		def foo(k,a,b,l,r): #[a,b)を調べる
			if b <= l or r <= a:
				return(0)
			elif a <= l and r <= b:
				return(li[k])
			else:
				return(
					foo(2*k,a,b,l,(r+l)//2)+foo(2*k+1,a,b,(r+l)//2,r)
					)

		return(foo(1,a,b+1,0,len(li)//2))

make(sta)
make(stb)
make(tta)
make(ttb)

for a,b,c,d in l:
	sa = get(sta,a-1,b-1)
	sb = get(stb,a-1,b-1)
	ta = get(tta,c-1,d-1)
	tb = get(ttb,c-1,d-1)


	if (sa+sb*2)%3 == (ta+tb*2)%3:
		print("YES")
	else:
		print("NO")





















Fixed submission:
S = list(input())
T = list(input())

# S=list("BBAAABA")
# T=list("BBBA")

q = int(input())

l = []
for i in range(q):
	l.append(list(map(int,input().split(" "))))


sta = [0 for i in range(len(S))]
stb = [0 for i in range(len(S))]

tta = [0 for i in range(len(T))]
ttb = [0 for i in range(len(T))]

if S[0] == "A":
	sta[0] = 1
else:
	stb[0] = 1

if T[0] == "A":
	tta[0] = 1
else:
	ttb[0] = 1

for i in range(1,len(S)):
	if S[i] == "A":
		sta[i] = sta[i-1]+1
		stb[i] = stb[i-1]
	else:
		sta[i] = sta[i-1]
		stb[i] = stb[i-1]+1

for i in range(1,len(T)):
	if T[i] == "A":
		tta[i] = tta[i-1]+1
		ttb[i] = ttb[i-1]
	else:
		tta[i] = tta[i-1]
		ttb[i] = ttb[i-1]+1


def get(l,a,b):
	if a == 0:
		return(l[b])
	else:
		return(l[b]-l[a-1])

for a,b,c,d in l:
	sa = get(sta,a-1,b-1)
	sb = get(stb,a-1,b-1)
	ta = get(tta,c-1,d-1)
	tb = get(ttb,c-1,d-1)


	if (sa+sb*2)%3 == (ta+tb*2)%3:
		print("YES")
	else:
		print("NO")