转自：c++ set容器排序准则 - 每天一点积累 - 博客园
#include <
set>
#include<algorithm>
using
namespace
std;
/*
Student结构体
*/
struct
Student {
string
name;
int
id;
int
score; };
/*
“仿函数”。为Student set指定排序准则
*/
class
studentSortCriterion {
public
:
/*类型要与set容器类型一致*/ bool operator() ( const Student *a, const Student *b) const { return (a->id == b->id) ? (a->score > b->score) :(a->id > b-> id); } }; int main() { set<Student*, studentSortCriterion> stuSet; set<Student*> stus; Student stu1, stu2,stu3; stu1.name = “ 张三 ” ; stu1.id = 2 ; stu1.score = 100 ; stu2.name = “ 李四 ” ; stu2.id = 1 ; stu2.score = 90 ; stu3.name = “ 小明 ” ; stu3.id = 3 ; stu3.score = 80 ; stuSet.insert(& stu1); stuSet.insert(& stu2); stuSet.insert(& stu3); Student stuTem; stuTem.score = 80 ; stuTem.id = 3 ; Student* stuTempPtr; set<Student*, studentSortCriterion> ::iterator iter; iter = stuSet.find(& stuTem); if(iter != stuSet.end()) { cout << (*iter)->name << endl; }
else { cout << “ Cannot find the student! ” << endl; } for(std:: set<Student*,studentSortCriterion>::iterator it = stuSet.begin();it!=stuSet.end();it++ ){ std::cout<<(*it)->name<< endl; } }
c++ set容器排序准则
转载两篇博客：
http://blog.csdn.net/lishuhuakai/article/details/51404214
http://blog.csdn.net/lihao21/article/details/6302196/
以下是实验代码：
#include <iostream>
/*类型要与set容器类型一致*/ bool operator() ( const Student *a, const Student *b) const { return (a->id == b->id) ? (a->score > b->score) :(a->id > b-> id); } }; int main() { set<Student*, studentSortCriterion> stuSet; set<Student*> stus; Student stu1, stu2,stu3; stu1.name = “ 张三 ” ; stu1.id = 2 ; stu1.score = 100 ; stu2.name = “ 李四 ” ; stu2.id = 1 ; stu2.score = 90 ; stu3.name = “ 小明 ” ; stu3.id = 3 ; stu3.score = 80 ; stuSet.insert(& stu1); stuSet.insert(& stu2); stuSet.insert(& stu3); Student stuTem; stuTem.score = 80 ; stuTem.id = 3 ; Student* stuTempPtr; set<Student*, studentSortCriterion> ::iterator iter; iter = stuSet.find(& stuTem); if(iter != stuSet.end()) { cout << (*iter)->name << endl; }
else { cout << “ Cannot find the student! ” << endl; } for(std:: set<Student*,studentSortCriterion>::iterator it = stuSet.begin();it!=stuSet.end();it++ ){ std::cout<<(*it)->name<< endl; } }
上面程序会根据学生ID先进行排名然后再根据分数进行排名，排序准则需要满足以下要求，摘自C++标准库第二版：
输出结果：
小明
小明
张三
李四
</div>
<div class = "postDesc">posted @ <span id="post-date">2017-04-12 17:01</span> <a href='https://www.cnblogs.com/hong2016/'>每天一点积累</a> 阅读(<span id="post_view_count">...</span>) 评论(<span id="post_comment_count">...</span>) <a href ="https://i.cnblogs.com/EditPosts.aspx?postid=6700146" rel="nofollow">编辑</a> <a href="#" onclick="AddToWz(6700146);return false;">收藏</a></div>
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