C语言如何建立链表并实现增删查改详解

#include <stdio.h>#include <stdlib.h>typedef struct { int *head; int length; int capacity;} Toslist; //Toslist类型//初始化顺序表Toslist initSeqlist() { Toslist list; list.length = 0; list.capacity = 5; list.head = (int *)malloc(10 * sizeof(int)); if (!list.head) { printf("初始化失败！/n"); exit(0); } return list;}

//打印顺序表void displayList(Toslist list) { for (int i = 0; i < list.length; i++) { printf("%d ", list.head[i]); } printf("/n");}

//插入元素Toslist add(Toslist list, int elem, int pos) { if (list.length == list.capacity) { int *temp = (int *)realloc(list.head, (list.capacity + 1) * sizeof(int));//判断空间是否足够，不够就另建链表//不直接用head而引入temp的作用：防止空间分配失败导致head失去原来的链表 if (!temp) {  list.head = temp;  list.capacity += 1; } } //插入位置及以后的元素后移 for (int i = list.length - 1; i >= pos; i--) { list.head[i + 1] = list.head[i]; } list.head[pos] = elem; list.length ++; return list; if (pos > list.length || pos < 0) printf("插入位置错误！/n"); return list;}

//删除元素Toslist delete(Toslist list, int pos) { for (int i = pos; i < list.length - 1; i++) { list.head[i] = list.head[i + 1]; } list.length--; return list; if (pos < 0 || pos > list.length) { printf("删除位置有误！/n"); return list; }}

//查int search(Toslist list, int elem) { //elem是查找的元素 //顺序查找 for (int i = 0; i < list.length; i++) { if (elem == list.head[i]) {  return i; } } return 0;}

//改Toslist modify(Toslist list, int elem, int val) { //val是要替换它的元素 int pos = search(list, elem); //获取要替换元素的位置 list.head[pos] = val; return list;}

int main() { Toslist list = initSeqlist(); int Addpos = -1, Addnum, Delpos, Serachnum,Modifynum; printf("请输入5个整数元素/n"); for (int i = 0; i < 5; i++) { scanf("%d", &list.head[i]); list.length++; } printf("顺序表中的元素有：/n"); displayList(list); //插入元素 printf("要在哪个元素后插入元素？/n"); while (Addpos < 0 || Addpos > list.length) { scanf("%d", &Addpos); if (Addpos < 0 || Addpos > list.length)  printf("请输入正确的位置！/n"); }; printf("请输入需要插入的元素：/n"); scanf("%d", &Addnum); printf("在顺序表的第%d个元素后插入元素%d得到/n", Addpos, Addnum); list = add(list, Addnum, Addpos); displayList(list); //删除元素 printf("要删除顺序表下标顺序中哪个元素？/n"); scanf("%d", &Delpos); printf("删除后得到：/n"); list = delete(list, Delpos); displayList(list); //查找 printf("请输入需要查找的元素/n"); scanf("%d", &Serachnum); int pos = search(list, Serachnum); if(pos) printf("元素%d的位置为第%d个/n", Serachnum, pos+1); if(!pos){ printf("表中无该元素/n"); } //修改 printf("请输入需要修改的元素：/n");scanf("%d",&Serachnum); printf("请输入要替换的数：/n");scanf("%d",&Modifynum); printf("将%d修改为%d得到：/n", Serachnum, Modifynum); list = modify(list, Serachnum, Modifynum); displayList(list); free(list.head); list.head = NULL; return 0;}