"""

def aplusb(self, a, b):

# write your code here, try to do it without arithmetic operators.

method = "seq"

if method == "xor":

while b > 0:

sum = a^b

carry = (a&b)<<1

a = sum

b = carry

return sum

elif method == "seq": #todo : http://stackoverflow.com/questions/37135106/what-is-good-way-to-negate-an-integer-in-binary-operation-in-python

len = sys.getsizeof(a)

mask_sign = 1<<(len-1)

neg = False

if ((a<0 and b>0 and abs(a)>abs(b)) or (a>0 and b<0 and abs(a)<abs(b)) or (a<0 and b<0)):

a = -a

b = -b

neg = True

carry = 0

sum = 0

mask = 1

while mask < mask_sign or mask < mask_sign:

cur_a = a & mask

cur_b = b & mask

if cur_a == mask and cur_b == mask:

if carry == 1:

sum |= mask

carry = 1

elif cur_a ==mask or cur_b ==mask:

if carry == 1:

carry = 1

else:

sum |= mask

carry = 0

else:

if carry:

sum |= mask

carry = 0

mask <<= 1

if neg:

sum = -sum