给你一个字符串，写出所有可能的ip

package main

import (
    "fmt"
    "os"
    "strconv"
)

func getip(source string) (ips []string) {

    length := len(source)
    if length > 12 || length < 4 {
        return nil
    }
    if length == 4 {
        ip := string(source[0]) + "." + string(source[1]) + "." + string(source[2]) + "." + string(source[3])
        ips = append(ips, ip)
    } else {
        s := source
        var ips_ [][]string
        //放置三个点
        for i := 0; i < length-1; i++ {
            if i > 2 {
                break
            }
            for j := i + 1; j < length-1; j++ {
                if j-i > 3 {
                    break
                }
                for k := j + 1; k < length-1; k++ {
                    //fmt.Println(i, j, k)
                    if k-j > 3 {
                        break
                    }
                    if len(s[k:]) <= 4 {
                        //fmt.Println(i, j, k)
                        var ipt []string
                        ipt = append(ipt, string(s[0:i+1]))
                        ipt = append(ipt, string(s[i+1:j+1]))
                        ipt = append(ipt, string(s[j+1:k+1]))
                        ipt = append(ipt, string(s[k+1:]))
                        ips_ = append(ips_, ipt)
                    }

                }
            }
        }
        for _, ip := range ips_ {
            for _, i := range ip {
                if ii, err := strconv.Atoi(i); err != nil || ii > 255 {
                    goto over
                }
            }
            ips = append(ips, ip[0]+"."+ip[1]+"."+ip[2]+"."+ip[3])
        over:
        }
    }
    return
}

func main() {
    fmt.Println("处理字符串：", os.Args[1])
    fmt.Println(getip(os.Args[1]))
}