Buggy python submission (verdict: Runtime Error):
N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
Cm = []
Cp = []
for i in range(N):
	if(A[i]-B[i]<0):
		Cm.append(A[i]-B[i])
	elif(A[i]-B[i]>0):
		Cp.append(A[i]-B[i])
Cm.sort()
Cp.sort()


if(len(Cm) == 0):
	print(0)
	exit(1)
if(sum(Cp)<abs(sum(Cm))):
	print(-1)
	exit(1)

j=0
i = 0
nowCp = int(Cp[len(Cp)-i-1])


while(j<len(Cm)):
	if(nowCp>=abs(Cm[j])):
		nowCp -= abs(Cm[j])
		j += 1
	elif(nowCp<abs(Cm[j]) and i<len(Cp)):
		i += 1
		nowCp += int(Cp[len(Cp)-i-1])

	else:
		break
	

if(j == len(Cm)):
	print(j+i+1)
else:
	print(-1)


Fixed submission:
N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
Cm = []
Cp = []
for i in range(N):
	if(A[i]-B[i]<0):
		Cm.append(A[i]-B[i])
	elif(A[i]-B[i]>0):
		Cp.append(A[i]-B[i])
Cm.sort()
Cp.sort()


if(len(Cm) == 0):
	print(0)
	exit(0)
if(sum(Cp)<abs(sum(Cm))):
	print(-1)
	exit(0)

j=0
i = 0
nowCp = int(Cp[len(Cp)-i-1])


while(j<len(Cm)):
	if(nowCp>=abs(Cm[j])):
		nowCp -= abs(Cm[j])
		j += 1
	elif(nowCp<abs(Cm[j]) and i<len(Cp)):
		i += 1
		nowCp += int(Cp[len(Cp)-i-1])

	else:
		break
	

if(j == len(Cm)):
	print(j+i+1)
else:
	print(-1)

Buggy python submission (verdict: Runtime Error):
N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
Cm = []
Cp = []
for i in range(N):
	if(A[i]-B[i]<0):
		Cm.append(A[i]-B[i])
	elif(A[i]-B[i]>0):
		Cp.append(A[i]-B[i])
Cm.sort()
Cp.sort()


if(len(Cm) == 0):
	print(0)
	exit(1)
if(sum(Cp)<abs(sum(Cm))):
	print(-1)
	exit(1)

j=0
i = 0
nowCp = int(Cp[len(Cp)-i-1])


while(j<len(Cm)):
	if(nowCp>=abs(Cm[j])):
		nowCp -= abs(Cm[j])
		j += 1
	elif(nowCp<abs(Cm[j])):
		i += 1
		nowCp += int(Cp[len(Cp)-i-1])

	else:
		break
	

if(j == len(Cm)):
	print(j+i+1)
else:
	print(-1)


Fixed submission:
N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
Cm = []
Cp = []
for i in range(N):
	if(A[i]-B[i]<0):
		Cm.append(A[i]-B[i])
	elif(A[i]-B[i]>0):
		Cp.append(A[i]-B[i])
Cm.sort()
Cp.sort()


if(len(Cm) == 0):
	print(0)
	exit(0)
if(sum(Cp)<abs(sum(Cm))):
	print(-1)
	exit(0)

j=0
i = 0
nowCp = int(Cp[len(Cp)-i-1])


while(j<len(Cm)):
	if(nowCp>=abs(Cm[j])):
		nowCp -= abs(Cm[j])
		j += 1
	elif(nowCp<abs(Cm[j]) and i<len(Cp)):
		i += 1
		nowCp += int(Cp[len(Cp)-i-1])

	else:
		break
	

if(j == len(Cm)):
	print(j+i+1)
else:
	print(-1)

Buggy python submission (verdict: Time Limit Exceeded):
N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
Cm = []
Cp = []
for i in range(N):
	if(A[i]-B[i]<0):
		Cm.append(A[i]-B[i])
	elif(A[i]-B[i]>0):
		Cp.append(A[i]-B[i])
Cm.sort()
Cp.sort()

cnt = 0
nowCp = 0
j = 0

for i in range(len(Cp)):

	if(sum(Cp)<abs(sum(Cm))):
		print(-1)
		break
	elif(len(Cm) == 0):
		print(0)
		break

	nowCp += int(Cp[len(Cp)-(i+1)])
	while(j<len(Cm)):
		if(nowCp>=abs(Cm[len(Cm)-j-1])):
			nowCp -= abs(Cm[len(Cm)-j-1])
			cnt += 1
			j += 1
		else:
			break

	if(cnt == len(Cm)):
		print(cnt+i+1)
		break

Fixed submission:
N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))
Cm = []
Cp = []
for i in range(N):
	if(A[i]-B[i]<0):
		Cm.append(A[i]-B[i])
	elif(A[i]-B[i]>0):
		Cp.append(A[i]-B[i])
Cm.sort()
Cp.sort()


if(len(Cm) == 0):
	print(0)
	exit(0)
if(sum(Cp)<abs(sum(Cm))):
	print(-1)
	exit(0)

j=0
i = 0
nowCp = int(Cp[len(Cp)-i-1])


while(j<len(Cm)):
	if(nowCp>=abs(Cm[j])):
		nowCp -= abs(Cm[j])
		j += 1
	elif(nowCp<abs(Cm[j]) and i<len(Cp)):
		i += 1
		nowCp += int(Cp[len(Cp)-i-1])

	else:
		break
	

if(j == len(Cm)):
	print(j+i+1)
else:
	print(-1)