定义结构体，通过动态数组和函数，实现对数据的输入、排序、输出

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

struct student
{
    int age;
    char name[20];
    float score;
};

void Inputstudent(struct student * p,int a);
void Outputstudent(struct student * p,int b);
void paixu(struct student * p,int c);

int main(void)
{
    int len;
    printf("请输入学生个数:\n");
    printf("len=");
    scanf("%d",&len);
    struct student * parr;
    parr = (struct student *)malloc(len * sizeof(struct student));
    Inputstudent(parr, len);

    paixu(parr, len);
    printf("\n\n\n");
    Outputstudent(parr, len);
    //paixu(parr, len);
    return 0;
}

void Inputstudent(struct student * p,int a)
{
    int i;
    for(i=0; i<a; i++)
    {
        printf("请输入第%d个学生的信息\n",i+1);
        printf("age=");
        scanf("%d",&p[i].age);
        printf("name=");
        scanf("%s",p[i].name);
        printf("score=");
        scanf("%f",&p[i].score);
    }
}

void Outputstudent(struct student * p,int b)
{
    printf("按成绩由高到低排序为：\n");
    int i;
    for(i=0; i<b; i++)
    {
        printf("第%d名学生的信息是：\n",i+1);

         printf("%d\n",p[i].age);

         printf("%s\n",p[i].name);

         printf("%3.2f\n",p[i].score);
    }
}

void paixu(struct student *p, int c)
{
    int i,j;
    struct student t;
    for(i=0; i<c-1; i++)
    {
        for(j=0; j<c-i-1; j++)
        {
            if(p[i].score < p[i+1].score)
            {
                t = p[i];
                p[i] = p[i+1];
                p[i+1] = t;
            }
        }
    }
}