Buggy python submission (verdict: Time Limit Exceeded):
import sys
from heapq import heappop as hpp, heappush as hp

readline = sys.stdin.readline
N = int(readline())
A = list(map(int, readline().split()))
B = list(map(int, readline().split()))

geta = 10**6        
Q = [-(B[i]*geta+i) for i in range(N)] + [0]
Q.sort()

ans = 0
cnt = 0
inf = 10**9+7
while cnt < N:
    b, idx = divmod(-hpp(Q), geta)
    bsec = Q[0]
    bsec = (-bsec)//geta
    a = A[idx]
    if b < a:
        ans = -1
        break
    bside = B[(idx+1)%N] + B[(idx-1)%N]
    kb = (1+(b-bsec)//bside)
    ka = (b-a)//bside
    k = min(ka, kb)
    B[idx] -= k*bside
    ans += k
    if B[idx] == a:
        cnt += 1
    elif k == 0:
        ans = -1
        break
    else:
        hp(Q, -(B[idx]*geta+idx))
print(ans)


Fixed submission:
import sys
from heapq import heappop as hpp, heappush as hp

readline = sys.stdin.readline
N = int(readline())
A = list(map(int, readline().split()))
B = list(map(int, readline().split()))

geta = 10**6        
Q = [-(B[i]*geta+i) for i in range(N)] + [0]
Q.sort()

ans = 0
cnt = 0
inf = 10**9+7
while cnt < N:
    b, idx = divmod(-hpp(Q), geta)
    a = A[idx]
    if b < a:
        ans = -1
        break
    bside = B[(idx+1)%N] + B[(idx-1)%N]
    kb = 1+(b-bside)//bside
    ka = (b-a)//bside
    k = min(ka, kb)
    B[idx] -= k*bside
    ans += k
    if B[idx] == a:
        cnt += 1
    elif k == 0:
        ans = -1
        break
    else:
        hp(Q, -(B[idx]*geta+idx))
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from heapq import heappop as hpp, heappush as hp

readline = sys.stdin.readline
N = int(readline())
A = list(map(int, readline().split()))
B = list(map(int, readline().split()))

geta = 10**6        
Q = [-(B[i]*geta+i) for i in range(N)]
Q.sort()

ans = 0
cnt = 0
inf = 10**9+7
while cnt < N:
    b, idx = divmod(-hpp(Q), geta)
    bsec = Q[0]
    bsec = (-bsec)//geta
    a = A[idx]
    if b < a:
        ans = -1
        break
    bside = B[(idx+1)%N] + B[(idx-1)%N]
    kb = (1+(b-bsec)//bside)
    ka = (b-a)//bside
    k = min(ka, kb)
    B[idx] -= k*bside
    ans += k
    if B[idx] == a:
        cnt += 1
        hp(Q, inf*geta)
    elif k == 0:
        ans = -1
        break
    else:
        hp(Q, -(B[idx]*geta+idx))
print(ans)

Fixed submission:
import sys
from heapq import heappop as hpp, heappush as hp

readline = sys.stdin.readline
N = int(readline())
A = list(map(int, readline().split()))
B = list(map(int, readline().split()))

geta = 10**6        
Q = [-(B[i]*geta+i) for i in range(N)] + [0]
Q.sort()

ans = 0
cnt = 0
inf = 10**9+7
while cnt < N:
    b, idx = divmod(-hpp(Q), geta)
    a = A[idx]
    if b < a:
        ans = -1
        break
    bside = B[(idx+1)%N] + B[(idx-1)%N]
    kb = 1+(b-bside)//bside
    ka = (b-a)//bside
    k = min(ka, kb)
    B[idx] -= k*bside
    ans += k
    if B[idx] == a:
        cnt += 1
    elif k == 0:
        ans = -1
        break
    else:
        hp(Q, -(B[idx]*geta+idx))
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from heapq import heappop as hpp, heappush as hp

readline = sys.stdin.readline
N = int(readline())
A = list(map(int, readline().split()))
B = list(map(int, readline().split()))

Q = [(-B[i], i) for i in range(N)]
Q.sort()

ans = 0
cnt = 0
inf = 10**9+7
while cnt < N:
    b, idx = hpp(Q)
    b = -b
    bsec, _ = Q[0]
    bsec = -bsec
    a = A[idx]
    if b < a:
        ans = -1
        break
    bside = B[(idx+1)%N] + B[(idx-1)%N]
    kb = (1+(b-bsec)//bside)
    ka = (b-a)//bside
    k = min(ka, kb)
    B[idx] -= k*bside
    ans += k
    if B[idx] == a:
        cnt += 1
        hp(Q, (inf, idx))
    elif k == 0:
        ans = -1
        break
    else:
        hp(Q, (-B[idx], idx))
print(ans)

Fixed submission:
import sys
from heapq import heappop as hpp, heappush as hp

readline = sys.stdin.readline
N = int(readline())
A = list(map(int, readline().split()))
B = list(map(int, readline().split()))

geta = 10**6        
Q = [-(B[i]*geta+i) for i in range(N)] + [0]
Q.sort()

ans = 0
cnt = 0
inf = 10**9+7
while cnt < N:
    b, idx = divmod(-hpp(Q), geta)
    a = A[idx]
    if b < a:
        ans = -1
        break
    bside = B[(idx+1)%N] + B[(idx-1)%N]
    kb = 1+(b-bside)//bside
    ka = (b-a)//bside
    k = min(ka, kb)
    B[idx] -= k*bside
    ans += k
    if B[idx] == a:
        cnt += 1
    elif k == 0:
        ans = -1
        break
    else:
        hp(Q, -(B[idx]*geta+idx))
print(ans)