add one approach

kanglicheng · web-flow · commit 1c9bb01d9b6f · 2018-03-08T15:24:00.000-08:00
diff --git a/Kangli/Trees/pathSumII.py b/Kangli/Trees/pathSumII.py
@@ -0,0 +1,14 @@
+class Solution(object):
+    def pathSum(self, root, sum):
+        result = []
+        self.dfs(root, sum, [], result)
+        return result
+    
+    def dfs(self, node, sum, path, res):
+        if not node:
+            return
+        if not node.left and not node.right:
+            if node.val == sum:
+                res.append(path + [node.val])
+        self.dfs(node.left, sum - node.val, path + [node.val], res)
+        self.dfs(node.right, sum - node.val, path + [node.val], res)
