Total Runtime: 553 ms

michaelhuang · michaelhuang · commit a37f9cf61ad8 · 2015-07-31T20:04:01.000+08:00
http://www.lintcode.com/en/problem/add-binary/
diff --git a/Add_Binary.py b/Add_Binary.py
@@ -0,0 +1,31 @@
+class Solution:
+    # @param {string} a a number
+    # @param {string} b a number
+    # @return {string} the result
+    def addBinary(self, a, b):
+        if len(a) < len(b): a, b = b, a
+        pa = len(a) - 1
+        pb = len(b) - 1
+        carry = 0
+        result = ''
+
+        while pb >= 0:
+            sum = int(a[pa]) + int(b[pb]) + carry
+            result = str(sum%2) + result
+            carry = sum / 2
+            pb -= 1
+            pa -= 1
+
+        while pa >= 0:
+            sum = int(a[pa]) + carry
+            result = str(sum%2) + result
+            carry = sum / 2
+            pa -= 1
+
+        if carry == 1: result = '1' + result
+        return  result
+
+if __name__ == '__main__':
+    a = Solution()
+    res = a.addBinary('110101','10010001011')
+    print res
