[已解决]c++sort()函数对存放对象指针向量排序的问题

VOGHOST

我想要用下面的代码实现对生生总成绩的排序但是编译不通过

vector<Student*> stu;        
bool cmp(Student* s1,Student* s2)                                //用来定义排序方式
        {
                return ((s1->Get_Sum_Score()) > (s2->Get_Sum_Score()));
        }
        void Sort_Class_Mates() { sort(stu.begin(), stu.end(), cmp); }        //学生排名

报出如下错误:
严重性        代码        说明        项目        文件        行        禁止显示状态
错误        C3867         “Class::cmp”: 非标准语法；请使用 "&" 来创建指向成员的指针        final        D:\Learning&Materials\Programming\c++\作业\final\final\final\student.h        169       
错误        C3867         “Class::cmp”: 非标准语法；请使用 "&" 来创建指向成员的指针        final        D:\Learning&Materials\Programming\c++\作业\final\final\final\student.h        169       
错误        C2672         “sort”: 未找到匹配的重载函数        final        D:\Learning&Materials\Programming\c++\作业\final\final\final\student.h        169       
错误        C2672         “sort”: 未找到匹配的重载函数        final        D:\Learning&Materials\Programming\c++\作业\final\final\final\student.h        169       
错误        C2780         “void std::sort(const _RanIt,const _RanIt)”: 应输入 2 个参数，却提供了 3 个        final        D:\Learning&Materials\Programming\c++\作业\final\final\final\student.h        169       
错误        C2780         “void std::sort(const _RanIt,const _RanIt)”: 应输入 2 个参数，却提供了 3 个        final        D:\Learning&Materials\Programming\c++\作业\final\final\final\student.h        169       

我向问下这种用法对普通数组可以，怎么我这样不行？？
有没有什么解决办法

最佳答案

月排行榜 / 总排行榜

我就是个弟弟

2019-6-21 11:09:05

#include <iostream>
#include <algorithm>
#include <ctime>
#include <cstdlib>
#include <vector>

using namespace std;

struct student
{
    int score;
};

void print(const student *pStu) {
    cout << pStu->score << ' ';
}

bool cmp(const student *stu1, const student *stu2) {
    return stu1->score < stu2->score;
}

int main(int, const char **)
{
    srand(time(nullptr));

    vector<student *> stu;
    student *stu1 = new student;
    student *stu2 = new student;
    student *stu3 = new student;

    stu1->score = rand() % 100;
    stu2->score = rand() % 100;
    stu3->score = rand() % 100;

    stu.push_back(stu1);
    stu.push_back(stu2);
    stu.push_back(stu3);

    for_each(begin(stu), end(stu), print);
    cout << endl;
    sort(begin(stu), end(stu), cmp);
    for_each(begin(stu), end(stu), print);
    cout << endl;

    delete stu1;
    delete stu2;
    delete stu3;
    stu1 = nullptr;
    stu2 = nullptr;
    stu3 = nullptr;

    return 0;
}

跳转到最佳答案楼层

我就是个弟弟

#include <iostream>
#include <algorithm>
#include <ctime>
#include <cstdlib>
#include <vector>

using namespace std;

struct student
{
    int score;
};

void print(const student *pStu) {
    cout << pStu->score << ' ';
}

bool cmp(const student *stu1, const student *stu2) {
    return stu1->score < stu2->score;
}

int main(int, const char **)
{
    srand(time(nullptr));

    vector<student *> stu;
    student *stu1 = new student;
    student *stu2 = new student;
    student *stu3 = new student;

    stu1->score = rand() % 100;
    stu2->score = rand() % 100;
    stu3->score = rand() % 100;

    stu.push_back(stu1);
    stu.push_back(stu2);
    stu.push_back(stu3);

    for_each(begin(stu), end(stu), print);
    cout << endl;
    sort(begin(stu), end(stu), cmp);
    for_each(begin(stu), end(stu), print);
    cout << endl;

    delete stu1;
    delete stu2;
    delete stu3;
    stu1 = nullptr;
    stu2 = nullptr;
    stu3 = nullptr;

    return 0;
}

我就是个弟弟

#include <iostream>
#include <algorithm>
#include <ctime>
#include <cstdlib>
#include <vector>

using namespace std;

struct student
{
    int score;
    bool operator() (const student *stu1, const student *stu2) {
        return stu1->score < stu2->score;
    }
};

void print(const student *pStu) {
    cout << pStu->score << ' ';
}

bool cmp(const student *stu1, const student *stu2) {
    return stu1->score < stu2->score;
}

int main(int, const char **)
{
    srand(time(nullptr));

    vector<student *> stu;
    student *stu1 = new student;
    student *stu2 = new student;
    student *stu3 = new student;

    stu1->score = rand() % 100;
    stu2->score = rand() % 100;
    stu3->score = rand() % 100;

    stu.push_back(stu1);
    stu.push_back(stu2);
    stu.push_back(stu3);

    for_each(begin(stu), end(stu), print);
    cout << endl;
    sort(begin(stu), end(stu), student());
    for_each(begin(stu), end(stu), print);
    cout << endl;

    delete stu1;
    delete stu2;
    delete stu3;
    stu1 = nullptr;
    stu2 = nullptr;
    stu3 = nullptr;

    return 0;
}

我就是个弟弟

参考:http://www.cplusplus.com/reference/algorithm/sort/?kw=sort

VOGHOST

我就是个弟弟 发表于 2019-6-21 11:15
参考:http://www.cplusplus.com/reference/algorithm/sort/?kw=sort

谢谢哈，好了，把函数提到外面就好了