struct ListNode { int val; struct ListNode *next;};struct ListN帮我解释这段代码
时间: 2024-04-27 14:23:52 浏览: 24
这段代码定义了一个名为 `ListNode` 的结构体,用于表示链表中的每一个节点。每个节点包含两个成员变量:一个整型变量 `val` 用于存储节点的值,一个指向下一个节点的指针 `next`。
具体来说,`int val` 表示当前节点存储的值,可以是任意整数;`struct ListNode *next` 表示指向下一个节点的指针,该指针是一个结构体指针类型,指向下一个节点的内存地址。
这里使用了 C 语言的结构体来表示链表,每个节点都是一个结构体,通过指针指向下一个节点,从而组成链表的形式。这种方式比较直观,易于理解,并且可以自由地插入或删除节点。
相关问题
补全如下代码:#include <stdio.h> #include <stdlib.h> struct ListNode { int data; struct ListNode *next; }; struct ListNode *readlist(); struct ListNode *deletem( struct ListNode *L, int m ); void printlist( struct ListNode *L ) { struct ListNode *p = L; while (p) { printf("%d ", p->data); p = p->next; } printf("\n"); } int main() { int m; struct ListNode *L = readlist(); scanf("%d", &m); L = deletem(L, m); printlist(L); return 0; }
代码如下:
```c
#include <stdio.h>
#include <stdlib.h>
struct ListNode {
int data;
struct ListNode *next;
};
struct ListNode *readlist();
struct ListNode *deletem(struct ListNode *L, int m);
void printlist(struct ListNode *L);
int main() {
int m;
struct ListNode *L = readlist();
scanf("%d", &m);
L = deletem(L, m);
printlist(L);
return 0;
}
struct ListNode *readlist() {
struct ListNode *head = NULL, *tail = NULL;
int n, val;
scanf("%d", &n);
while (n--) {
scanf("%d", &val);
struct ListNode *node = (struct ListNode*)malloc(sizeof(struct ListNode));
node->data = val;
node->next = NULL;
if (!head) {
head = node;
tail = node;
} else {
tail->next = node;
tail = node;
}
}
return head;
}
struct ListNode *deletem(struct ListNode *L, int m) {
struct ListNode *head = NULL, *tail = NULL;
while (L) {
if (L->data != m) {
struct ListNode *node = (struct ListNode*)malloc(sizeof(struct ListNode));
node->data = L->data;
node->next = NULL;
if (!head) {
head = node;
tail = node;
} else {
tail->next = node;
tail = node;
}
}
L = L->next;
}
return head;
}
void printlist(struct ListNode *L) {
struct ListNode *p = L;
while (p) {
printf("%d ", p->data);
p = p->next;
}
printf("\n");
}
```
该代码实现了链表的基本操作,包括创建链表、删除指定元素、打印链表等。其中,`readlist()`函数用于创建链表,`deletem()`函数用于删除指定元素,`printlist()`函数用于打印链表。主函数中,通过调用`readlist()`函数创建链表,并读入需要删除的元素,然后调用`deletem()`函数进行删除操作,最后调用`printlist()`函数打印删除后的链表。
用C语言改写,将打印输出的结果中重复的数去掉#include <stdio.h>#include <stdlib.h>struct ListNode { int val; struct ListNode *next;};struct ListNode* mergeList(struct ListNode* l1, struct ListNode* l2){ struct ListNode* dummy = (struct ListNode*)malloc(sizeof(struct ListNode)); // 新建一个虚拟头节点 dummy->val = 0; dummy->next = NULL; struct ListNode* cur = dummy; while (l1 && l2) { if (l1->val <= l2->val) { cur->next = l1; l1 = l1->next; } else { cur->next = l2; l2 = l2->next; } cur = cur->next; } if (l1) cur->next = l1; // 将剩余的节点加入到新链表中 if (l2) cur->next = l2; return dummy->next;}int main() { int n, m, num; scanf("%d%d", &n, &m); struct ListNode* l1 = (struct ListNode*)malloc(sizeof(struct ListNode)); struct ListNode* l2 = (struct ListNode*)malloc(sizeof(struct ListNode)); struct ListNode* p1 = l1; struct ListNode* p2 = l2; for (int i = 0; i < n; i++) { scanf("%d", &num); p1->next = (struct ListNode*)malloc(sizeof(struct ListNode)); p1->next->val = num; p1->next->next = NULL; p1 = p1->next; } for (int i = 0; i < m; i++) { scanf("%d", &num); p2->next = (struct ListNode*)malloc(sizeof(struct ListNode)); p2->next->val = num; p2->next->next = NULL; p2 = p2->next; } struct ListNode* res = mergeList(l1->next, l2->next); while (res) { printf("%d ", res->val); res = res->next; } return 0;}
以下是用 C 语言改写,并去掉重复数的代码:
#include <stdio.h>
#include <stdlib.h>
struct ListNode {
int val;
struct ListNode *next;
};
struct ListNode* mergeList(struct ListNode* l1, struct ListNode* l2){
struct ListNode* dummy = (struct ListNode*)malloc(sizeof(struct ListNode)); // 新建一个虚拟头节点
dummy->val = 0;
dummy->next = NULL;
struct ListNode* cur = dummy;
while (l1 && l2) {
if (l1->val <= l2->val) {
cur->next = l1;
l1 = l1->next;
} else {
cur->next = l2;
l2 = l2->next;
}
cur = cur->next;
}
if (l1) cur->next = l1; // 将剩余的节点加入到新链表中
if (l2) cur->next = l2;
return dummy->next;
}
int main() {
int n, m, num;
scanf("%d%d", &n, &m);
struct ListNode* l1 = (struct ListNode*)malloc(sizeof(struct ListNode));
struct ListNode* l2 = (struct ListNode*)malloc(sizeof(struct ListNode));
struct ListNode* p1 = l1;
struct ListNode* p2 = l2;
for (int i = 0; i < n; i++) {
scanf("%d", &num);
p1->next = (struct ListNode*)malloc(sizeof(struct ListNode));
p1->next->val = num;
p1->next->next = NULL;
p1 = p1->next;
}
for (int i = 0; i < m; i++) {
scanf("%d", &num);
p2->next = (struct ListNode*)malloc(sizeof(struct ListNode));
p2->next->val = num;
p2->next->next = NULL;
p2 = p2->next;
}
struct ListNode* res = mergeList(l1->next, l2->next);
// 去除重复数
int hash[10001] = {0}; // 哈希表,假设节点值范围在 [0, 10000]
struct ListNode* cur = res;
struct ListNode* pre = NULL;
while (cur) {
if (hash[cur->val]) { // 如果当前节点值已经出现过,则删除当前节点
pre->next = cur->next;
free(cur);
cur = pre->next;
} else { // 如果当前节点值没有出现过,则将其加入哈希表,并继续遍历下一个节点
hash[cur->val] = 1;
pre = cur;
cur = cur->next;
}
}
// 输出结果
cur = res;
while (cur) {
printf("%d ", cur->val);
cur = cur->next;
}
// 释放内存
cur = res;
while (cur) {
struct ListNode* temp = cur;
cur = cur->next;
free(temp);
}
return 0;
}