Initial commit

python/Misc/Python program to find whether it contains an additive sequence or not.py

@@ -0,0 +1,27 @@
+class Solution(object):  
+# DFS: iterative implement.  
+    def is_additive_number(self, num):  
+        length = len(num)  
+        for i in range(1, int(length/2+1)):  
+            for j in range(1, int((length-i)/2 + 1)):  
+                first, second, others = num[:i], num[i:i+j], num[i+j:]  
+                if self.isValid(first, second, others):  
+                    return True  
+        return False  
+  
+    def isValid(self, first, second, others):  
+        if ((len(first) > 1 and first[0] == "0") or  
+                (len(second) > 1 and second[0] == "0")):  
+            return False  
+        sum_str = str(int(first) + int(second))  
+        if sum_str == others:  
+            return True  
+        elif others.startswith(sum_str):  
+            return self.isValid(second, sum_str, others[len(sum_str):])  
+        else:  
+            return False  
+  
+if __name__ == "__main__":  
+    print(Solution().is_additive_number('66121830'))  
+    print(Solution().is_additive_number('51123'))  
+    print(Solution().is_additive_number('235813'))