Create nested_list_weight_sum.py

yingl · web-flow · commit 7037ed2661cf · 2019-02-19T21:50:37.000+08:00
diff --git a/nested_list_weight_sum.py b/nested_list_weight_sum.py
@@ -0,0 +1,39 @@
+"""
+This is the interface that allows for creating nested lists.
+You should not implement it, or speculate about its implementation
+
+class NestedInteger(object):
+    def isInteger(self):
+        # @return {boolean} True if this NestedInteger holds a single integer,
+        # rather than a nested list.
+
+    def getInteger(self):
+        # @return {int} the single integer that this NestedInteger holds,
+        # if it holds a single integer
+        # Return None if this NestedInteger holds a nested list
+
+    def getList(self):
+        # @return {NestedInteger[]} the nested list that this NestedInteger holds,
+        # if it holds a nested list
+        # Return None if this NestedInteger holds a single integer
+"""
+
+
+class Solution(object):
+    # @param {NestedInteger[]} nestedList a list of NestedInteger Object
+    # @return {int} an integer
+    @staticmethod
+    def _depthSum(nestedList, count, level=1): # 递归，level记录深度
+        for i in nestedList:
+            if i.isInteger():
+                count[0] += i.getInteger() * level
+            else:
+                Solution._depthSum(i.getList(), count, level+1)
+        
+    def depthSum(self, nestedList):
+        # Write your code here
+        count = [0]
+        Solution._depthSum(nestedList, count)
+        return count[0]
+        
+# easy: https://www.lintcode.com/problem/nested-list-weight-sum
