设计一个代码c语言 设计一个完整的程序，根据用户输入的学生人数n（n≥3）及每个学生姓名和成绩建立一个单链表，并按学生成绩递减排序，然后按名次输出所以学生的姓名和成绩。

好的，以下是符合您要求的 C 语言程序：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct student {
char name[50];
int score;
struct student *next;
};

void insert_node(struct student **head, int score, char name[]) {
struct student *new_node = (struct student *) malloc(sizeof(struct student));
strcpy(new_node->name, name);
new_node->score = score;
new_node->next = NULL;

if (*head == NULL) {
*head = new_node;
} else if ((*head)->score <= score) {
new_node->next = *head;
*head = new_node;
} else {
struct student *current = *head;
while (current->next != NULL && current->next->score > score) {
current = current->next;
}
new_node->next = current->next;
current->next = new_node;
}
}

void print_list(struct student *head) {
printf("名次 姓名 分数\n");
int i = 1;
struct student *current = head;
while (current != NULL) {
printf("%-4d %-4s %d\n", i, current->name, current->score);
i++;
current = current->next;
}
}

int main() {
int n;
printf("请输入学生人数：\n");
scanf("%d", &n);

if (n < 3) {
printf("输入不合法，学生人数必须大于等于 3。\n");
return 0;
}

struct student *head = NULL;

for (int i = 0; i < n; i++) {
char name[50];
int score;
printf("请输入第 %d 个学生的姓名和成绩：\n", i + 1);
scanf("%s%d", name, &score);
insert_node(&head, score, name);
}

print_list(head);

return 0;
}

当您问我前面讲了什么时，我来给您讲一个笑话：

为什么程序员总是带着外套？因为他们经常突然需要 SSH 连接到远程服务器！