利用c语言里的链表删除大于k的节点，以0为结尾，输入k和链表，输出删除后的链表。（只会c语言，还没有学习c++）
不知道为什么代码运行错误，我是根据书上的链表删除的公式写的删除函数的，但是完全没发删除，感觉很苦恼
例子：
输入：2000
2001 2002 1999 1998 2021 1997 0
输出：1999 1998 1997
```c
#include
您的代码中存在一些问题：
在 delect() 函数中，当链表头的值大于 k 时，您直接让 head 指向当前节点 p，但是却没有释放原来的头节点空间，导致内存泄漏。可以先将当前节点 p 存到 p1 中，再释放 p0。
在 print() 函数中，每输出一个节点的值后都应该将 p 指向下一个节点，否则会造成死循环输出。
在输出节点的值时，应该加上换行符，否则多个值会输出在同一行，不易阅读。
下面是修改后的代码，您可以参考一下：
#include <stdio.h>
#include <stdlib.h>
struct cell {
int year;
struct cell *next;
};
struct cell *build(void) {
struct cell *head, *p, *tmp;
int n;
head = p = tmp = NULL;
scanf("%d", &n);
if (n == 0) {
return head;
}
p = (struct cell*)malloc(sizeof(struct cell));
p->year = n;
p->next = NULL;
head = p;
scanf("%d", &n);
while (n != 0) {
tmp = (struct cell*)malloc(sizeof(struct cell));
tmp->year = n;
tmp->next = NULL;
p->next = tmp;
p = p->next;
scanf("%d", &n);
}
return head;
}
struct cell *delect(struct cell *head, int k) {
struct cell *p, *p0, *p1;
p = head;
p0 = NULL;
if (head == NULL) {
return head;
}
while (p->year > k) {
p1 = p;
p = p->next;
free(p1);
}
head = p;
while (p != NULL) {
if (p->year > k) {
p1 = p;
p = p->next;
free(p1);
p0->next = p;
} else {
p0 = p;
p = p->next;
}
}
return head;
}
void print(struct cell *head) {
struct cell *p;
p = head;
if (head == NULL) {
printf("NULL\n");
return;
}
while (p != NULL) {
printf("%d\n", p->year);
p = p->next;
}
}
void release(struct cell *head) {
struct cell *p0, *p;
p = head;
while (p != NULL) {
p0 = p;
p = p->next;
free(p0);
}
}
int main() {
struct cell *head;
int k;
scanf("%d", &k);
head = build();
head = delect(head, k);
print(head);
release(head);
return 0;
}
改动处见注释，供参考：
#include<stdio.h>
#include<malloc.h>
struct cell
{
int year;
struct cell* next;
};
struct cell* build(void)
{
struct cell* head, * p, * tmp;
int n;
head = p = tmp = NULL;
//scanf("%d", &n);
//if (n == 0)
//{
// return head;
//}
//p = (struct cell*)malloc(sizeof(struct cell));
//p->year = n;
//p->next = NULL;
//head = p;
//scanf("%d", &n);
while (1) //(n != 0) //修改
{
scanf("%d", &n); //修改
if (n == 0) break; //修改
tmp = (struct cell*)malloc(sizeof(struct cell));
tmp->year = n;
tmp->next = NULL;
if (head == NULL)
head = tmp;
else
p->next = tmp;
p = tmp; //p = p->next; 修改
//scanf("%d", &n); 修改
}
return head;
}//;
struct cell* delect(struct cell* head, int k)
{
struct cell* p, * p0, * p1;
p = head;
p0 = NULL;
if (head == NULL) { return head; }
//while (p->year > k) 修改
//{
// p = p->next; free(p0->next); p0->next = p;
//}
//head = p;
while (p != NULL)
{
if (p->year > k) {
if (p == head){
head = head->next;
free(p);
p = head;
}
else {
p0->next = p->next;
free(p);
p = p0;
}
}
else {
p0 = p;
p = p->next;
}
//p = p->next; free(p0->next); p0->next = p; } 修改
}
return head;
}//;
void print(struct cell* head)
{
struct cell* p;
p = head;
if (head == NULL) {
printf("NULL");
return;
}
while (p != NULL)
{
printf("%d", p->year);
if (p->next != NULL) { printf(" "); }
p = p->next; //修改
}
}
void release(struct cell* head)
{
struct cell* p0, * p;
p = head;
while (p != NULL)
{
p0 = p;
p = p->next;
free(p0);
}
}
int main()
{
struct cell* head;
int k;
scanf("%d", &k);
head = build();
head = delect(head, k);
print(head);
release(head);
return 0;
}