利用循环列表实现ABCDEFGHIJKLMNOPQRSTUVWXYZ
输入:3
输出:DEFGHIJKLMNOPQRSTUVWXYZABC
输入:-3
输出:XYZABCDEFGHIJKLMNOPQRSTUVW
代码如下:
#include<stdio.h>
#include<stdlib.h>
#define OK 1
#define ERROR 0
typedef char ElemType;
typedef int Status;
typedef struct DualNode
{
ElemType data;
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;
}
(*L)->next = (*L)->prior = NULL;
p = (*L);
for(i=0;i<26;i++)
{
q=(DualNode *)malloc(sizeof(DualNode));
if(!q)
{
return ERROR;
}
q->data = '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;
}while(++i);
}
}
int main()
{
DuLinkList L;
int i,n;
InitList(&L);
printf("please enter an integer: ");
scanf("%d",&n);
printf("\n");
Caesar(&L,n);
for(i=0;i<26;i++)
{
L = L->next;
printf("%c",L->data);
}
return 0;
}