结构体快排

转载自：https://blog.csdn.net/qingyuanluofeng/article/details/47159193

/*
题目:
学生成绩排序：成绩从低到高，姓名字母从低到高（区分大小写），年龄从低到高排序
输入:
3
abc 20 99
bcd 19 97
bed 20 97

输出:
bcd 19 97
bed 20 97
abc 20 99

易错点:
1对于字符指针，scanf("%s",ps[i].sName)不需要取地址符
2对于名字，要指定大小，否则内存访问非法,char sName[128];而不是定义char* sName;
3int strcmp(const char* string1,const char* string2); <0:前<后


得分:0
*/

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

typedef struct Student
{
    //Student(char* name,int age,int grade):sName(name),iAge(age),iGrade(grade){}
    //char* sName;//就是这里出错了，没有具体制定多大
    //char* sName;

    //法二，用重载操作符operator<的方法做
    bool operator < (const Student& stu) const
    {
        if(iGrade != stu.iGrade)
        {
            return iGrade < stu.iGrade;
        }
        else
        {
            if(sName != stu.sName)
            {
                return strcmp(sName,stu.sName) < 0 ? true:false;
            }
            else
            {
                return iAge < stu.iAge;
            }
        }
    }
    char sName[128];
    int iAge;
    int iGrade;
}Student;

bool compare(struct Student stuA,struct Student stuB)
{
    if(stuA.iGrade < stuB.iGrade)
    {
        return true;
    }
    else if(stuA.iGrade == stuB.iGrade )
    {
        if(stuA.sName!=stuB.sName)
        {
            return strcmp(stuA.sName,stuB.sName) < 0 ? true:false ;//这里中断了
        }
        else
        {
            return stuA.iAge < stuB.iAge;
        }
    }
    else
    {
        return false;
    }
}


int partition(Student* ps,int low,int high)
{
    Student stu = ps[low];
    while(low < high)
    {
        //while(low < high && compare(stu,ps[high]))//法1
        while(low < high && stu < ps[high])
        {
            high--;
        }
        ps[low] = ps[high];
        //while(low < high && compare(ps[low],stu))//法1
        while(low < high && ps[low] < stu)
        {
            low++;
        }
        ps[high] = ps[low];
    }
    ps[low] = stu;
    return low;
}

void quickSort(Student* ps,int low,int high)
{
    if(low < high)
    {
        int iPos = partition(ps,low,high);
        quickSort(ps,low,iPos-1);
        quickSort(ps,iPos+1,high);
    }
}

void print(Student* ps,int iNum)
{
    for(int i = 0;i < iNum ;i++)
    {
        printf("%s %d %d
",ps[i].sName,ps[i].iAge,ps[i].iGrade);
    }
}


int main(int argc,char* argv[])
{
    int iNum;
    while(EOF!=scanf("%d",&iNum))
    {
        //ptrStu ps = (ptrStu)malloc(iNum*sizeof(Student));
        Student* ps = (Student*)malloc(iNum*sizeof(Student));
        //Student ps[100];
        for(int i = 0; i < iNum; i++)
        {
            //char* sName;
            //int iAge,iGrade;
            //scanf("%s %d %d",&ps[i].sName,&ps[i].iAge,&ps[i].iGrade); //关键字符串不需要取地址，因为它本身就是一个地址，否则就是取地址的地址了
            scanf("%s %d %d",ps[i].sName,&ps[i].iAge,&ps[i].iGrade);
            //Student *stu = (Student*)malloc(1*sizeof(Student))(sName,iAge,iGrade);
            //ps[i] = stu;//难道是因为出了这里就不存在了
        }
        //printf("%s
",ps[1].sName);
        //print(ps,iNum);
        quickSort(ps,0,iNum-1);
        print(ps,iNum);
        free(ps);
    }
    //getchar();
    return 0;
}