From a9132cb7ffa71ae9631a90a3d1ebcc12edd9d62b Mon Sep 17 00:00:00 2001
From: X-shuffle <53906918+X-shuffle@users.noreply.github.com>
Date: Sun, 20 Jun 2021 16:39:35 +0800
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200093.=E5=A4=8D=E5=8E=9FIP?=
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添加 0093.复原IP地址 go版本
---
 problems/0093.复原IP地址.md | 41 +++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/problems/0093.复原IP地址.md b/problems/0093.复原IP地址.md
index a8b9a215..1c8e4069 100644
--- a/problems/0093.复原IP地址.md
+++ b/problems/0093.复原IP地址.md
@@ -367,6 +367,47 @@ var restoreIpAddresses = function(s) {
     }
 };
 ```
+Go：
+> 回溯（对于前导 0的IP（特别注意s[startIndex]=='0'的判断，不应该写成s[startIndex]==0，因为s截取出来不是数字））
+
+```go
+func restoreIpAddresses(s string) []string {
+	var res,path []string
+	backTracking(s,path,0,&res)
+	return res
+}
+func backTracking(s string,path []string,startIndex int,res *[]string){
+	//终止条件
+	if startIndex==len(s)&&len(path)==4{
+		tmpIpString:=path[0]+"."+path[1]+"."+path[2]+"."+path[3]
+		*res=append(*res,tmpIpString)
+	}
+	for i:=startIndex;i<len(s);i++{
+		//处理
+		path:=append(path,s[startIndex:i+1])
+		if i-startIndex+1<=3&&len(path)<=4&&isNormalIp(s,startIndex,i){
+			//递归
+			backTracking(s,path,i+1,res)
+		}else {//如果首尾超过了3个，或路径多余4个，或前导为0，或大于255，直接回退
+			return
+		}
+        //回溯
+		path=path[:len(path)-1]
+	}
+}
+func isNormalIp(s string,startIndex,end int)bool{
+	checkInt,_:=strconv.Atoi(s[startIndex:end+1])
+	if end-startIndex+1>1&&s[startIndex]=='0'{//对于前导 0的IP（特别注意s[startIndex]=='0'的判断，不应该写成s[startIndex]==0，因为s截取出来不是数字）
+		return false
+	}
+	if checkInt>255{
+		return false
+	}
+	return true
+}
+
+```
+
 
 -----------------------
 * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw)