Question

C语言编程题，求助大佬解答

用指针对有序数组进行插入和删除，使得它仍然有序

Answer 1

#include <iostream>
using namespace std;

struct Node
{
int elem;
Node* next;
};

struct List
{
Node* head = NULL;
};

//查找前驱节点
Node* find_pre(List list, int elem)
{
if (!list.head) return NULL;
Node* node = list.head;
while (node->next && node->next->elem < elem) node = node->next;
return node;
}

//插入节点
void ins_elem(List &list, int elem)
{
Node* pre = find_pre(list, elem);
if (!pre)
{
list.head = (Node*)malloc(sizeof(Node)); //头结点暂不存放值
list.head->next = (Node*)malloc(sizeof(Node));
list.head->next->elem = elem;
list.head->next->next = NULL;
return;
}

Node* new_node = (Node*)malloc(sizeof(Node));
new_node->elem = elem;
new_node->next = pre->next;
pre->next = new_node;
}

//删除节点
void del_elem(List &list, int elem)
{
Node* pre = find_pre(list, elem);
if (!pre) return;
while (pre->next->elem == elem)
{
Node* next = pre->next;
pre->next = next->next;
free(next);
}

}

//遍历链表
void traverse(List list)
{
if (!list.head) return;
Node* node = list.head->next;
while (node)
{
cout << node->elem << " ";
node = node->next;
}
cout << endl;
}

//销毁链表
void destory(List &list)
{
if (!list.head) return;
Node* node = list.head->next;
while (node)
{
Node* next = node->next;
free(node);
node = next;
}
}

int main()
{
int arr[5] = { 1, 2, 2, 4, 5 };
List list;//声明链表
for (int i = 0; i < 5; i++)
{
ins_elem(list, arr[i]);
}
traverse(list);
del_elem(list, 2);
traverse(list);
destory(list);
return 0;
}

Answer 2

题目是不是出错了，应该是使用指针对有序数组进行插入和排序吧，使用链表？这个怎么理解？

追问

不好意思，题目修改过来了，能帮忙回答了吗？

追答

不好意思，这几天没上百度。现在还需要吗？

粘贴代码超长，用图。