Buggy python submission (verdict: Time Limit Exceeded):
import heapq
import bisect

N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

F = sorted(F, reverse = True)
A = sorted(A)
flg = 0
lst = []

for i in range(N):
	if A[i] == 0 or F[i] == 0:
		break
	else:
		lst.insert(bisect.bisect_left(lst, [A[i] * F[i], F[i]]),[A[i] * F[i], F[i]]) 
		# heapq.heappush(heap, [- A[i] * F[i], F[i]])
		
for i in range(K):
	popped = lst.pop(-1)
	popped[0] -= popped[1]
	lst.insert(bisect.bisect_left(lst, popped), popped)

print(lst[-1][0])	

Fixed submission:
N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

A.sort()
F.sort(reverse = True)

ng = -1
ok = 10 ** 12

while ok - ng > 1:
	mid = (ok + ng) // 2
	ctr = 0
	for i in range(N):
		ctr += max(0, A[i] - mid // F[i])
	if ctr <= K:
		ok = mid
	else:
		ng = mid

print(ok)

Buggy python submission (verdict: Time Limit Exceeded):
import heapq

N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

F = sorted(F, reverse = True)
A = sorted(A)
flg = 0
heap = []

for i in range(N):
	if A[i] == 0 or F[i] == 0:
		break
	else:
		heapq.heappush(heap, [- A[i] * F[i], F[i]])
	
for i in range(K):
	score, tmp_F = heapq.heappop(heap)
	s_score, s_tmp_F = heapq.heappop(heap)
	
	
	if score < 0:
		while s_score >= score:
			score += tmp_F
		heapq.heappush(heap, [score, tmp_F])
		heapq.heappush(heap, [s_score, s_tmp_F])
	else:
		flg = 1
		break
		
if flg:
	print(0)
else:
	ret = heapq.heappop(heap)
	print(-1 * ret[0])	


Fixed submission:
N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

A.sort()
F.sort(reverse = True)

ng = -1
ok = 10 ** 12

while ok - ng > 1:
	mid = (ok + ng) // 2
	ctr = 0
	for i in range(N):
		ctr += max(0, A[i] - mid // F[i])
	if ctr <= K:
		ok = mid
	else:
		ng = mid

print(ok)

Buggy python submission (verdict: Time Limit Exceeded):
import heapq

N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

F = sorted(F, reverse = True)
A = sorted(A)
flg = 0
heap = []

for i in range(N):
	if A[i] == 0 or F[i] == 0:
		break
	else:
		heapq.heappush(heap, [- A[i] * F[i], A[i], F[i]])
	
for i in range(K):
	score, tmp_A, tmp_F = heapq.heappop(heap)
	if tmp_A > 0:
		tmp_A -= 1
		heapq.heappush(heap, [- tmp_A * tmp_F, tmp_A, tmp_F])
	else:
		flg = 1
		break
		
if flg:
	print(0)
else:
	ret = heapq.heappop(heap)
	print(-1 * ret[0])	


Fixed submission:
N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

A.sort()
F.sort(reverse = True)

ng = -1
ok = 10 ** 12

while ok - ng > 1:
	mid = (ok + ng) // 2
	ctr = 0
	for i in range(N):
		ctr += max(0, A[i] - mid // F[i])
	if ctr <= K:
		ok = mid
	else:
		ng = mid

print(ok)

Buggy python submission (verdict: Time Limit Exceeded):
import heapq
import sys
input = sys.stdin.readline
N, K = map(int, input().split())
A = sorted(list(map(int, input().split())))
F = sorted(list(map(int, input().split())), reverse = True)

flg = 0
heap = []

for i in range(N):
	heapq.heappush(heap, [- A[i] * F[i], F[i]])
	
for i in range(K):
	score, tmp_F = heapq.heappop(heap)
	if score != 0:
		score += tmp_F
		heapq.heappush(heap, [score, tmp_F])
	else:
		flg = 1
		break
		
if flg:
	print(0)
else:
	ret = heapq.heappop(heap)
	print(-1 * ret[0])	

Fixed submission:
N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

A.sort()
F.sort(reverse = True)

ng = -1
ok = 10 ** 12

while ok - ng > 1:
	mid = (ok + ng) // 2
	ctr = 0
	for i in range(N):
		ctr += max(0, A[i] - mid // F[i])
	if ctr <= K:
		ok = mid
	else:
		ng = mid

print(ok)

Buggy python submission (verdict: Time Limit Exceeded):
import heapq

N, K = map(int, input().split())
A = sorted(list(map(int, input().split())))
F = sorted(list(map(int, input().split())), reverse = True)

flg = 0
heap = []

for i in range(N):
	heapq.heappush(heap, [- A[i] * F[i], F[i]])
	
for i in range(K):
	score, tmp_F = heapq.heappop(heap)
	if score != 0:
		score += tmp_F
		heapq.heappush(heap, [score, tmp_F])
	else:
		flg = 1
		break
		
if flg:
	print(0)
else:
	ret = heapq.heappop(heap)
	print(-1 * ret[0])	


Fixed submission:
N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

A.sort()
F.sort(reverse = True)

ng = -1
ok = 10 ** 12

while ok - ng > 1:
	mid = (ok + ng) // 2
	ctr = 0
	for i in range(N):
		ctr += max(0, A[i] - mid // F[i])
	if ctr <= K:
		ok = mid
	else:
		ng = mid

print(ok)

Buggy python submission (verdict: Time Limit Exceeded):
import heapq

N, K = map(int, input().split())
A = sorted(list(map(int, input().split())))
F = sorted(list(map(int, input().split())), reverse = True)

flg = 0
heap = []

for i in range(N):
	heapq.heappush(heap, [- A[i] * F[i], F[i]])
	
for i in range(K):
	score, tmp_F = heapq.heappop(heap)
	if score != 0:
		score += tmp_F
		heapq.heappush(heap, [score, tmp_F])
	else:
		flg = 1
		break
		
if flg:
	print(0)
else:
	ret = heapq.heappop(heap)
	print(-1 * ret[0])	

Fixed submission:
N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

A.sort()
F.sort(reverse = True)

ng = -1
ok = 10 ** 12

while ok - ng > 1:
	mid = (ok + ng) // 2
	ctr = 0
	for i in range(N):
		ctr += max(0, A[i] - mid // F[i])
	if ctr <= K:
		ok = mid
	else:
		ng = mid

print(ok)

Buggy python submission (verdict: Time Limit Exceeded):
import heapq

N, K = map(int, input().split())
A = sorted(list(map(int, input().split())))
F = sorted(list(map(int, input().split())), reverse = True)

flg = 0
heap = []

for i in range(N):
	heapq.heappush(heap, [- A[i] * F[i], A[i], F[i]])
	
for i in range(K):
	score, tmp_A, tmp_F = heapq.heappop(heap)
	if tmp_A > 0:
		tmp_A -= 1
		heapq.heappush(heap, [- tmp_A * tmp_F, tmp_A, tmp_F])
	else:
		flg = 1
		break
		
if flg:
	print(0)
else:
	ret = heapq.heappop(heap)
	print(-1 * ret[0])	

Fixed submission:
N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

A.sort()
F.sort(reverse = True)

ng = -1
ok = 10 ** 12

while ok - ng > 1:
	mid = (ok + ng) // 2
	ctr = 0
	for i in range(N):
		ctr += max(0, A[i] - mid // F[i])
	if ctr <= K:
		ok = mid
	else:
		ng = mid

print(ok)

Buggy python submission (verdict: Time Limit Exceeded):
import heapq

N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

F = sorted(F, reverse = True)
A = sorted(A)
flg = 0
heap = []

for i in range(N):
	heapq.heappush(heap, [- A[i] * F[i], A[i], F[i]])
	
for i in range(K):
	score, tmp_A, tmp_F = heapq.heappop(heap)
	if tmp_A > 0:
		tmp_A -= 1
		heapq.heappush(heap, [- tmp_A * tmp_F, tmp_A, tmp_F])
	else:
		flg = 1
		break
		
if flg:
	print(0)
else:
	ret = heapq.heappop(heap)
	print(-1 * ret[0])	

Fixed submission:
N, K = map(int, input().split())
A = list(map(int, input().split()))
F = list(map(int, input().split()))

A.sort()
F.sort(reverse = True)

ng = -1
ok = 10 ** 12

while ok - ng > 1:
	mid = (ok + ng) // 2
	ctr = 0
	for i in range(N):
		ctr += max(0, A[i] - mid // F[i])
	if ctr <= K:
		ok = mid
	else:
		ng = mid

print(ok)