创建一个简单的单链表

1.头文件的Slist.h的代码

#pragma once
#include<stdio.h>
#include<stdlib.h>
#include<assert.h>
#include<string.h>
typedef int SListint;
typedef struct Slist//单链表
{SListint data;struct Slist* next;
}SL;//尾插
void SlistPushBank(SL** plist,SListint x);
//头插
void SlistPushFront(SL** plist, SListint x);
//打印
void Slist_print(SL** plist);
//尾删
void SlistPopBank(SL** plist);
//头删
void SlistPopFront(SL** plist);
//查找
SL* SlistFind(SL* plist, SListint x);
//在pos位置前插入x
void SlistInsert(SL** plist, SL* pos, SListint x);
//删除pos位置的值
void SListFrase(SL** plist, SL* pos);
//销毁
void SlistDestroyed(SL** plist);

2.源文件Slist.h的函数实现

#include"Slist.h"
//申请空间函数
SL* kuorong(SListint x)
{SL* newnode = (SL*)malloc(sizeof(SL));newnode->data = x;newnode->next = NULL;return newnode;
}
//尾插
void SlistPushBank(SL** plist, SListint x)
{assert(plist);SL* newnode = kuorong(x);if (*plist == NULL){*plist = newnode;}else { SL* pcur = *plist; while (pcur->next != NULL){pcur = pcur->next;}pcur->next = newnode;}
}
//头插
void SlistPushFront(SL** plist, SListint x)
{assert(plist);SL* newnode = kuorong(x);newnode->next = *plist;*plist = newnode;
}
//打印
void Slist_print(SL** plist)
{SL* ret = *plist;while (ret)//ret != NULL{printf("%d->", ret->data);ret = ret->next;}printf("NULL\n");
}
//尾删
void SlistPopBank(SL** plist)
{assert(*plist);//*plist == NULL   1if ((*plist)->next == NULL)//    2{free(*plist);*plist = NULL;}else                      //     3{SL* ret = *plist;SL* pcur = *plist;while (ret->next != NULL){pcur = ret;ret = ret->next;}free(ret);pcur->next = NULL;}
}
//头删
void SlistPopFront(SL** plist)
{assert(*plist);if ((*plist)->next == NULL){free(*plist);}else{SL* ret = (*plist)->next;free(*plist);*plist = ret;}
}
//查找
SL* SlistFind(SL* plist, SListint x)
{SL* ret = plist;while (ret){if (x == ret->data){return ret;}ret = ret->next;}return NULL;
}
//在pos之前插入数据
void SlistInsert(SL** plist, SL* pos, SListint x)
{assert(plist);if (pos == *plist){SlistPushFront(plist, x);//如果只有一个数值，那么调用头插，不然会报错}else{SL* ret = *plist;SL* newnode = kuorong(x);while (ret->next != pos){ret = ret->next;}newnode->next = ret->next;ret->next = newnode;}
}
//删除pos位置的值
void SListFrase(SL** plist, SL* pos)
{assert(plist);if (pos == *plist){SlistPopFront(plist);}else{SL* ret = *plist;while (ret->next != pos){ret = ret->next;}ret->next = pos->next;free(pos);}
}
//销毁
void SlistDestroyed(SL** plist)
{SL* ret = *plist;while (ret){SL* cur = ret->next;free(ret);ret = cur;}*plist = NULL;
}

3.测试test.c的代码
 

#define _CRT_SECURE_NO_WARNINGS 1
#include"Slist.h"
void menu()
{printf("*************************\n");printf("1.尾插             2.头插\n");printf("3.尾删             4.头删\n");printf("5.打印链表     6.查找元素\n");printf("7pos前插入      8.删除pos\n");printf("9.销毁        10.退出菜单\n");printf("*************************\n");
}
int main()
{int input = 0, x = 0, y = 0;SL* plist = NULL;do{menu();printf("请输入你的选择\n");scanf("%d", &input);switch (input){case 1:printf("\n请输入尾插的数值，输入-1结束\n");do{scanf("%d", &x);if (x != -1){SlistPushBank(&plist, x);}} while (x != -1);break;case 2:printf("请输入头插的数值，输入-1结束\n");do{scanf("%d", &x);if (x != -1){SlistPushFront(&plist, x);}} while (x != -1);break;case 3:SlistPopBank(&plist);printf("尾删成功\n");break;case 4:SlistPopFront(&plist);printf("头删成功\n");break;case 5:Slist_print(&plist);break;case 6:printf("请输入你要查找的元素\n");scanf("%d", &x);SL* ret = SlistFind(plist,x);if (ret != NULL){printf("找到了\n");}else{printf("没找到\n");}break;case 7:printf("请输入你要在哪个pos之前插入\n");scanf("%d", &x);SL* retpos1 = SlistFind(plist,x);if (retpos1 == NULL){printf("要插入的pos数值不存在\n");exit(1);}else {printf("请输入要插入的数值\n");scanf("%d", &y);SlistInsert(&plist, retpos1, y);printf("插入成功\n");}break;case 8:printf("请输入你要删除的pos数值\n");scanf("%d", &x);SL* retpos2 = SlistFind(plist,x);if (retpos2 == NULL){printf("要删除的pos节点不存在\n");exit(1);}else{SListFrase(&plist, retpos2);printf("删除成功\n");}break;case 9:SlistDestroyed(&plist);printf("销毁成功\n");break;case 10:input = -1;printf("退出中....\n");break;default:printf("请选择1-10的方法\n");break;}} while (input != -1);return 0;
}