使用qsort对结构体指针数组根据compare规则进行排序-白红宇

使用qsort对结构体指针数组根据compare规则进行排序

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发布时间：2019-05-10

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有一个记录学生信息的文件，每一行记录一名学生的信息，格式如下：

学号\t 姓名\t 性别\t 分数 1\t 分数 2\t 分数 3\n.

要求：

（1）读取文件的内容，串成一个链表。

（2）按照总分递减排序将结果保存到原文件

（3）使用命令行参数读取文件

#define _CRT_SECURE_NO_WARNINGS#define USR_NAME_LEN 20#define N 10#include 
   
    #include 
    
     #include 
     
      typedef struct student{
   	int usr_id;	char usr_name[USR_NAME_LEN];	int gender;	double course_score_1;	double course_score_2;	double course_score_3;	struct student* pNext;}Student_t, *pStudent_t;int compare(const void* p1, const void* p2){
   	pStudent_t* ptr1 = (pStudent_t*)p1;	pStudent_t* ptr2 = (pStudent_t*)p2;	if (((*ptr1)->course_score_1 + (*ptr1)->course_score_2 + (*ptr1)->course_score_3) >((*ptr2)->course_score_1 + (*ptr2)->course_score_2 + (*ptr2)->course_score_3))	{
   		return 1;	}	else	{
   		return 0;	}}int main(int argc, char** argv){
   	FILE* fp;	pStudent_t phead = NULL;	int cnt = 0;	if (argc != 2)	{
   		printf("error args\n");		return -1;		system("pause");	}	fp = fopen(argv[1], "r+");	if (NULL == fp)	{
   		perror("fopen");		return -1;	}	pStudent_t tmp = (pStudent_t)calloc(1, sizeof(Student_t));	while ((fscanf(fp, "%d\t%s\t%d\t%lf\t%lf\t%lf\n", &tmp->usr_id, tmp->usr_name,&tmp->gender,&tmp->course_score_1, &tmp->course_score_2, &tmp->course_score_3)) == 6)	{
   		pStudent_t pnew = (pStudent_t)calloc(1, sizeof(Student_t));		pnew->usr_id = tmp->usr_id;		strcpy(pnew->usr_name, tmp->usr_name);		pnew->gender = tmp->gender;		pnew->course_score_1 = tmp->course_score_1;		pnew->course_score_2 = tmp->course_score_2;		pnew->course_score_3 = tmp->course_score_3;	if (phead == NULL)	{
   		phead = pnew;	}	else	{
   		pStudent_t ppreNode = phead;		pStudent_t pcurNode = phead;	while (pcurNode)	{
   		ppreNode = pcurNode;		pcurNode = pcurNode->pNext;	}	ppreNode->pNext = pnew;	pnew->pNext = NULL;	}		cnt++;	}	fclose(fp);	pStudent_t* pArr = (pStudent_t*)calloc(cnt, sizeof(pStudent_t));	pStudent_t pCur = phead;	for (int i = 0; i < cnt; i++)	{
   		pArr[i] = pCur;		pCur = pCur->pNext;	}	pCur = NULL;	qsort(pArr, cnt, sizeof(pStudent_t), compare);	fp = fopen(argv[1], "w+");	if (NULL == fp)	{
   		perror("fopen");		return -1;	}	for (int i = 0; i < cnt; i++)	{
   		fprintf(fp, "%d\t%s\t%d\t%f\t%f\t%f\n", pArr[i]->usr_id, pArr[i]->usr_name, pArr[i]->gender,pArr[i]->course_score_1, pArr[i]->course_score_2, pArr[i]->course_score_3);	}	fclose(fp);	while (phead != NULL)	{
   		pCur = phead;		phead = phead->pNext;		free(pCur);		pCur = NULL;	}	free(pArr);	system("pause");	return 0;}