Given two binary strings, return their sum (also a binary string).
Example,
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| a = "11"
b = "1"
Return "100".
|
Solution
(Add-Binary.py) download
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| class Solution(object):
def addBinary(self, a, b):
"""
:type a: str
:type b: str
:rtype: str
"""
if a == None:
return b
if b== None:
return a
ret = ""
add = 0
i = len(a)-1
j = len(b)-1
while i >= 0 and j >= 0:
l = int(a[i])
r = int(b[j])
ret = str((l+r+add)%2)+ret
add = (l+r+add)/2
i -=1
j -=1
while i >= 0:
l = int(a[i])
ret = str((l+add)%2) + ret
add = (l+add)/2
i -= 1
while j >= 0:
r = int(b[j])
ret = str((r+add)%2) + ret
add = (r+add)/2
j -= 1
# don't forget add
if add ==0:
return ret
else:
return "1"+ret
|