first problems

easy/67 Add Binary/Solution.py

@@ -0,0 +1,25 @@
+class Solution:
+    def addBinary(self, a: str, b: str) -> str:
+        a = a[::-1]
+        b = b[::-1]
+        carry = 0
+        c = ""
+        for i in range(max(len(a), len(b))):
+            d = carry + int(a[i]) + int(b[i])
+            if d == 3:
+                c = c + "1"
+                carry = 1
+            if d == 2:
+                c = c + "0"
+                carry = 1
+            if d == 1:
+                c = c + "1"
+                carry = 0
+            if d == 0:
+                c = c + "0"
+                carry = 0
+            else:
+                print(d)
+                raise Exception
+
+        return(c[::-1])

easy/67 Add Binary/testing.py

@@ -0,0 +1,5 @@
+import Solution
+
+s = Solution.Solution()
+
+print(s.addBinary("11", "1"))