class Solution:

def divide(self, dividend, divisor):

positive = (dividend < 0) is (divisor < 0)

dividend = abs(dividend)

divisor = abs(divisor)

res=0

while dividend>=divisor:

temp,i = divisor,1

while dividend>=temp:

# 这个循环不加，只用外层循环也可以；这个循环主要是为了加速代码，使减数/除数以2的指数增加

# 这样的话，时间复杂度就不是O(dividend/divisor)而是O[log_2_(dividend/divisor)]?

dividend -= temp

res+=i

i<<=1

temp<<=1

if not positive:

res = -res

return min(max(-2147483648, res),2147483648)

import time

start = time.clock()

TestCase = 25

divisor = -5

ExpectOutput = -5

solu = Solution()#先对类初始化，才能进行调用

temp = solu.divide(TestCase, divisor)

if (temp == ExpectOutput):

print('right')

else:

print('wrong')

print(temp)

elapsed = (time.clock() - start)

print("Time used:", elapsed)