From 2e8ba2bbb8e27132129d83c64795ba8feaed39d2 Mon Sep 17 00:00:00 2001
From: X-shuffle <53906918+X-shuffle@users.noreply.github.com>
Date: Sat, 19 Jun 2021 20:25:29 +0800
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200216.=E7=BB=84=E5=90=88?=
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添加 0216.组合总和III go版本
---
 problems/0216.组合总和III.md | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/problems/0216.组合总和III.md b/problems/0216.组合总和III.md
index 9f75b23d..67e67ad0 100644
--- a/problems/0216.组合总和III.md
+++ b/problems/0216.组合总和III.md
@@ -284,6 +284,37 @@ class Solution:
 
 Go：
 
+
+> 回溯+减枝
+
+```go
+func combinationSum3(k int, n int) [][]int {
+    var track []int// 遍历路径
+    var result [][]int// 存放结果集
+    backTree(n,k,1,&track,&result)
+    return result
+}
+func backTree(n,k,startIndex int,track *[]int,result *[][]int){
+    if len(*track)==k{
+        var sum int
+        tmp:=make([]int,k)
+        for k,v:=range *track{
+            sum+=v
+            tmp[k]=v
+        }
+        if sum==n{
+            *result=append(*result,tmp)
+        }
+        return
+    }
+    for i:=startIndex;i<=9-(k-len(*track))+1;i++{//减枝（k-len(*track)表示还剩多少个可填充的元素）
+        *track=append(*track,i)//记录路径
+        backTree(n,k,i+1,track,result)//递归
+        *track=(*track)[:len(*track)-1]//回溯
+    }
+}
+```
+
 javaScript:
 
 ```js