package main

import "fmt"

type node struct {
	val      int
	pre, nex *node
}

type MyCircularDeque struct {
	cap, size  int
	head, rear *node
}

func Constructor(k int) MyCircularDeque {
	head, rear := &node{}, &node{}
	head.nex = rear
	rear.pre = head
	return MyCircularDeque{
		cap:  k,
		head: head,
		rear: rear,
	}
}

func (this *MyCircularDeque) InsertFront(value int) bool {
	if this.size == this.cap {
		return false
	} else {
		node := node{
			val: value,
		}
		nex := this.head.nex
		this.head.nex, node.pre, node.nex, nex.pre = &node, this.head, nex, &node
		this.size++
		return true
	}
}

func (this *MyCircularDeque) InsertLast(value int) bool {
	if this.size == this.cap {
		return false
	} else {
		node := node{
			val: value,
		}
		fmt.Println(this.rear)
		pre := this.rear.pre
		this.rear.pre, node.pre, node.nex, pre.nex = &node, pre, this.rear, &node
		this.size++
		return true
	}
}

func (this *MyCircularDeque) DeleteFront() bool {
	if this.size == 0 {
		return false
	} else {
		this.head.nex, this.head.nex.nex.pre = this.head.nex.nex, this.head
		this.size--
		return true
	}
}

func (this *MyCircularDeque) DeleteLast() bool {
	if this.size == 0 {
		return false
	} else {
		this.rear.pre, this.rear.pre.pre.nex = this.rear.pre.pre, this.rear
		this.size--
		return true
	}
}

func (this *MyCircularDeque) GetFront() int {
	if this.size == 0 {
		return -1
	} else {
		return this.head.nex.val
	}
}

func (this *MyCircularDeque) GetRear() int {
	if this.size == 0 {
		return -1
	} else {
		return this.rear.pre.val
	}
}

func (this *MyCircularDeque) IsEmpty() bool {
	return this.size == 0
}

func (this *MyCircularDeque) IsFull() bool {
	return this.size == this.cap
}