单向循环链表创建、遍历、插入、删除、查找（按位置，按元素值）、清空、销毁

SinglyLinkedCirculayList.h

#include "stdafx.h"#include "iostream"using namespace std;typedef struct LNode {int data;struct LNode *next;}LNode, *LinkedList;//创建链表bool createLinkedList(LinkedList &L, int i) {if (i < 1){cout << "输入不合法！" << endl;exit(EXIT_FAILURE);}L = (LinkedList)malloc(sizeof(LNode));if (!L){cout << "内存分配失败!" << endl;exit(EXIT_FAILURE);}LinkedList p, q;L->next = L;p = L;int j;for (j = 0; j < i; j++){q = (LinkedList)malloc(sizeof(LNode));if (!q){cout << "内存分配失败！" << endl;exit(EXIT_FAILURE);}cout << "请输入第" << j + 1 << "个元素：";cin >> q->data;p->next = q;q->next = L;p = q;}return true;}//获取链表的长度int getListLength(LinkedList &L) {if (L->next == L){cout << "链表为空" << endl;return 0;}LinkedList p;p = L;int j = 0;while (p->next != L){j++;p = p->next;}return j;}//打印链表void printLinkedList(LinkedList &L) {LinkedList p;p = L;if (L->next == L){cout << "链表为空！" << endl;exit(EXIT_FAILURE);}for (int i = 0; i < getListLength(L); i++){p = p->next;cout << p->data << "  ";}cout << endl;}//在第i个位置之前插入元素bool insertListElem(LinkedList &L, int i, int num) {if (i<1 || i>getListLength(L)){cout << "输入不合法！" << endl;exit(EXIT_FAILURE);}LinkedList p, q;p = L;for (int j = 0; j < i - 1; j++)   //定位到要插入结点的前一个{p = p->next;}q = (LinkedList)malloc(sizeof(LNode));if (!q){cout << "内存分配失败！" << endl;exit(EXIT_FAILURE);}q->data = num;q->next = p->next;p->next = q;return true;}//删除第i个元素bool deleteListElem(LinkedList &L, int i) {if (i<1 || i>getListLength(L)){cout << "输入不合法！" << endl;exit(EXIT_FAILURE);}LinkedList p,q;p = L;int j;for (j = 0; j < i - 1; j++)   //定位到要删除的结点的前一个{p = p->next;}q = p->next;p->next = p->next->next;free(q);return true;}//查找并返回第i个位置的元素int getElem(LinkedList &L, int i) {if (i<1 || i>getListLength(L)){cout << "输入不合法！" << endl;exit(EXIT_FAILURE);}LinkedList p;p = L;int j;for (j = 0; j < i; j++){p = p->next;}return p->data;}//在链表中查找节点值等于num的位置，并返回int searchElem(LinkedList &L, int num) {LinkedList p;p = L->next;int j = 1;while ((p->data != num) && (j <= getListLength(L))){p = p->next;j++;}if (j <= getListLength(L)){return j;}else{cout << "查找无该值！" << endl;return false;}}//销毁链表bool destroylinkedlist(LinkedList &L) {LinkedList p, q;p = q = L->next;while (p != L){p = p->next;free(q);q = p;}free(L);return true;}//清空链表bool clearList(LinkedList &L) {LinkedList p, q;p =q= L->next;if (L == NULL){return false;}while (p != L){p = p->next;free(q);q = p;}L->next = L;return true;}

main.cpp

#include "stdafx.h"#include "SinglyLinkedCirculayList.h"int main(){LinkedList list1;int length;cout << "请输入要创建的链表的长度：";cin >> length;createLinkedList(list1, length);cout << "当前链表为：";printLinkedList(list1);int i, elem;cout << "要插入的位置为：";cin >> i;cout << "要插入的元素的大小为：";cin >> elem;insertListElem(list1,i,elem);cout << "当前链表为：";printLinkedList(list1);cout << "要删除的元素的位置为：";cin >> i;deleteListElem(list1,i);cout << "当前链表为：";printLinkedList(list1);cout << "要查找的元素位置为：";cin >> i;cout << "该位置元素的值为：";cout<<getElem(list1,i)<<endl;cout << "要查找的元素大小为：";cin >> elem;cout << "该元素所在的位置为：";cout << searchElem(list1,elem)<<endl;cout << "清空链表";clearList(list1);cout << "打印当前链表：";printLinkedList(list1);system("pause");return 0;}