双向链表实现卡萨密码

#define _CRT_SECURE_NO_DEPRECATE
#include <iostream>
#include <cstdio>
#include<cstdlib>

#define OK 1
#define ERROR 0

typedef char ElemType;
typedef int Status;
typedef struct DualNode
{
	ElemType date;
	struct  DualNode *prior;
	struct  DualNode *next;

}DualNode,*DuLinkList;

Status InitList(DuLinkList *L)
{
	DualNode *p,*q;
	int i;
	*L = (DuLinkList)malloc(sizeof(DualNode));
	if (!(*L))
	{
		return ERROR;
	}
	//生成头结点
	(*L)->next = (*L)->prior = NULL;
	p = (*L);
	for ( i = 0; i < 26; i++)
	{
		q = (DualNode*)malloc(sizeof(DualNode));
		if (!q)
		{
			return ERROR;
		}
		q->date = 'A'+i;
		q->prior = p;
		q->next = p->next;
		p->next = q;

		p = q;

	}
	p->next = (*L)->next;
	(*L)->next->prior = p;
	return OK;
}
void Caesar(DuLinkList *L, int i)
{
	if (i>0)
	{
		do
		{
			(*L) = (*L)->next;
		} while (--i);
	}
	if (i<0)
	{
		do
		{
			(*L)=(*L)->next->prior->prior;
		} while (++i);
	}
}
int main()
{
	DuLinkList L;
	int i,n;
	InitList(&L);
	printf("请输入一个整数:");
	scanf("%d", &n);
	Caesar(&L, n);
	for ( i = 0; i < 26; i++)
	{
		L = L->next;
		printf("%c",L->date);
	}
	system( "pause");
	return 0;
}