目标：

1. 实现一个循环单链表
2. 实现一个循环双链表

代码实现：

package main

import (
    "fmt"
    "time"
)

// 单向链表结点
type LNode struct {
    data interface{}
    next *LNode
}

func main() {
    // 循环单链表遍历
    LoopList := getLoopList()
    tmpLoopList := LoopList
    for tmpLoopList != nil {
        fmt.Println(tmpLoopList.data)
        tmpLoopList = tmpLoopList.next
        time.Sleep(time.Second)
    }
}

func getLoopList() *LNode {
    node := new(LNode)
    node.data = 0
    first := node
    for i:=1; i<10; i++ {
        temp := new(LNode)
        temp.data = i
        node.next = temp
        node = temp
    }
    node.next = first
    return first
}

package main

import (
    "fmt"
    "time"
)

// 双向链表结点
type RNode struct {
    data interface{}
    prev *RNode
    next *RNode
}

func main() {
    // 循环双链表
    ring := getRing()
    // 顺时针遍历
    tmpRing := ring
    for tmpRing != nil {
        fmt.Println(tmpRing.data)
        tmpRing = tmpRing.next
        time.Sleep(time.Second)
    }
    //// 逆时针遍历
    //tmpRing2 := ring
    //for tmpRing2 != nil {
    //  fmt.Println(tmpRing2.data)
    //  tmpRing2 = tmpRing2.prev
    //  time.Sleep(time.Second)
    //}
}

func getRing() *RNode {
    node := new(RNode)
    node.data = 0
    first := node
    for i := 1; i < 10; i++ {
        temp := new(RNode)
        temp.data = i
        temp.prev = node
        node.next = temp
        node = temp
    }

    node.next = first
    first.prev = node
    return first
}