双向链表及约瑟夫环代码

双向链表

//注意：该文件操作的链表为带头结点双向链表，头结点数据为-1

#include <stdio.h>

#include <stdlib.h>

#include <time.h>

#define OK 1

#define ERROR 0

 

typedef int data_t;

typedef struct DulNode

{

data_t data;

struct DulNode *prior;

struct DulNode *next;

}DulNode,*DuLinkList;

 

int GetElem(DuLinkList L,int i,data_t *data)//读取双向链表的第i个元素

{

int j;

DuLinkList p;

p = L;

j = 1;

while(p && j<i)

{

p = p->next;//让p指向下一个节点

j++;

}

if(!p)

{

printf("第%d个位置不存在！\n",i);

return ERROR;

}

*data = p->data;

return OK;

}

 

int ListInsert(DuLinkList L,int i,data_t e)

{

int j;

DuLinkList p,s;

p=L;

j=1;

while(p && j<i)

{

p=p->next;

j++;

}

if(!p)

{

printf("第%d个位置不存在！\n",i);

return ERROR;

}

s=(DuLinkList)malloc(sizeof(DulNode));

s->data=e;

s->prior=p;

s->next=p->next;

p->next->prior=s;

p->next=s;

return OK;

}

 

int ListDelete(DuLinkList L,int i,data_t *e)

{

int j;

DuLinkList p;

p=L;

j=1;

while(p->next && j<=i)

{

p=p->next;

j++;

}

if(!(p->next))

{

printf("第%d个位置不存在！\n",i);

return ERROR;

}

*e=p->data;

p->prior->next=p->next;

p->next->prior=p->prior;

free(p);

p=NULL;

return OK;

}

 

DuLinkList CreateEmptyList()

{

DuLinkList p;

p = (DuLinkList)malloc(sizeof(DulNode));

if(p==NULL)

{

perror("CreateEmptyList error");

exit(0);

}

p->prior=NULL;

p->next=NULL;

p->data=-1;

return p;

}

 

DuLinkList CreateList(DuLinkList L,int n)

{

DuLinkList p,r;

int i;

srand(time(NULL));

r = L;

for(i=0;i<n;i++)

{

p = (DuLinkList)malloc(sizeof(DulNode));

p->data = rand()%100+1;

r->next = p;

p->prior = r;

r = p;

}

r->next = NULL;

return L;

}

 

int ClearList(DuLinkList L)

{

DuLinkList p,q;

p=L->next;

while(p)

{

q=p->next;

free(p);

p=q;

}

L->next=NULL;

return OK;

}

 

int PrintList(DuLinkList L)

{

    DuLinkList p=L;

    while(p)

    {

 

        printf("%d\t",p->data);

        p=p->next;

    }

    printf("\n");

    return OK;

}

 

int main()

{

    /*

    DuLinkList head;

head = CreateEmptyList();

    head = CreateList(head,15);

    int i=5;

    data_t data=12;

    PrintList(head);

    printf("插入head第%d个位置，数据为%d\n",i,data);

    ListInsert(head,i,data);

    printf("插入后链表为：\n");

    PrintList(head);

    i=8;

    ListDelete(head,i,&data);

    printf("删除head第%d个位置，删除数据为%d\n",i,data);

    printf("删除后链表为：\n");

    PrintList(head);

    if(ClearList(head)==OK)

    {

        printf("head已被成功删除！\n");

    }

    */

    return 0;

}

约瑟夫环代码

#include <stdio.h>

#include <stdlib.h>

 

typedef int data_t;

 

/* use a cycle linked list without header node */

typedef struct node_t

{

data_t data;

struct node_t *next;

} linknode_t, *linklist_t;

 

int main()

{

int i, n, m, k;

linklist_t p, q;

printf("total N people will join this suicide game, please input N:");

scanf("%d", &n);

printf( "people stand in a circle, assume everyone is assigned\n"

"a sequence number from 1 to %d.\n"\

"which one would you like to start the number off (1~%d):", n, n);

scanf("%d", &k);

printf("every Xth people should kill himself, please decide the X:");

scanf("%d", &m);

 

if (n < 1 || k > n || m < 1) {

printf("input error!\n");

return -1;

}

 

printf("game is starting ...\n");

 

/* added the first one */

p = q = (linklist_t)malloc(sizeof(linknode_t));

p->data = 1;

 

/* added other left people */

for (i = 2; i <= n; i++) {

q->next = (linklist_t)malloc(sizeof(linknode_t));

q = q->next;

q->data = i;

}

/* complete the circle */

q->next = p;

/* find the people ahead of #k */

q = p;

while (q->next != p) {

if (q->next->data == k)

break;

q = q->next;

}

 

while (q->next != q) { /* till the last one */

 

/* every m people */

for (i = 0; i < m - 1; i++)

{

q = q->next;

}

 

/* kill the m-th people */

p = q->next;

q->next = p->next;

printf("%-2d was killed\n", p->data);

free(p);

}

 

/* kill the last one */

printf("%-2d was alive\n", q->data);

free(q);

 

return 0;

}