From 340277131853eefaf669a47a7b092227632e71f9 Mon Sep 17 00:00:00 2001
From: jojoo15 <75017412+jojoo15@users.noreply.github.com>
Date: Tue, 25 May 2021 10:16:43 +0200
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200039.=E7=BB=84=E5=90=88?=
 =?UTF-8?q?=E6=80=BB=E6=95=B0=20python3=E7=89=88=E6=9C=AC?=
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添加 0039.组合总数 python3版本
---
 problems/0039.组合总和.md | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/problems/0039.组合总和.md b/problems/0039.组合总和.md
index d025eaef..e3e79295 100644
--- a/problems/0039.组合总和.md
+++ b/problems/0039.组合总和.md
@@ -271,8 +271,25 @@ class Solution {
 ```
 
 Python：
-
-
+```python3
+class Solution:
+    def combinationSum(self, candidates: List[int], target: int) -> List[List[int]]:
+        res = []
+        path = []
+        def backtrack(candidates,target,sum,startIndex):
+            if sum > target: return 
+            if sum == target: return res.append(path[:])
+            for i in range(startIndex,len(candidates)):
+                if sum + candidates[i] >target: return  #如果 sum + candidates[i] > target 就终止遍历
+                sum += candidates[i] 
+                path.append(candidates[i])
+                backtrack(candidates,target,sum,i)  #startIndex = i:表示可以重复读取当前的数
+                sum -= candidates[i]  #回溯
+                path.pop()  #回溯
+        candidates = sorted(candidates)  #需要排序
+        backtrack(candidates,target,0,0)
+        return res
+```
 Go：