为LeetCode第437、455题增加了Python语言支持

problems/437.path-sum-iii.md

@@ -117,8 +117,9 @@ var pathSum = function (root, sum) {
 
 ## 代码
 
-- 语言支持：JS
+- 语言支持：JS, Python
 
+JS code:
 ```js
 /*
  * @lc app=leetcode id=437 lang=javascript
@@ -164,6 +165,39 @@ var pathSum = function (root, sum) {
 };
 ```
 
+Python Code:
+```python
+import collections
+'''
+class TreeNode:
+    def __init__(self, val=0, left=None, right=None):
+        self.val = val
+        self.left = left
+        self.right = right
+'''
+class Solution:
+    def helper(self,root,acc,target,hashmap):
+        if not root:
+            return 0
+        count=0
+        acc+=root.val
+        if acc==target:
+            count+=1
+        if acc-target in hashmap:
+            count+=hashmap[acc-target]
+        hashmap[acc]+=1
+        if root.left:
+            count+=self.helper(root.left,acc,target,hashmap)
+        if root.right:
+            count+=self.helper(root.right,acc,target,hashmap)
+        hashmap[acc]-=1
+        return count
+
+    def pathSum(self, root: Optional[TreeNode], targetSum: int) -> int:
+        hashmap=collections.defaultdict(lambda:0)
+        return self.helper(root,0,targetSum,hashmap)
+```
+
 **复杂度分析**
 
 - 时间复杂度：$O(N)$

problems/455.AssignCookies.md

@@ -61,8 +61,9 @@ https://leetcode-cn.com/problems/assign-cookies/
 
 ## 代码
 
-语言支持：JS
+语言支持：JS, Python
 
+JS Code:
 ```js
 /**
  * @param {number[]} g
@@ -90,6 +91,21 @@ const findContentChildren = function (g, s) {
 };
 ```
 
+Python Code:
+```python
+class Solution:
+    def findContentChildren(self, g: List[int], s: List[int]) -> int:
+        g.sort()
+        s.sort()
+        count=gIdx=sIdx=0
+        while gIdx<len(g) and sIdx<len(s):
+            if s[sIdx]>=g[gIdx]:
+                gIdx+=1
+                count+=1
+            sIdx+=1
+        return count
+```
+
 ***复杂度分析***
 
 - 时间复杂度：由于使用了排序，因此时间复杂度为 O(NlogN)