vector 结构体类型 使用 排序

如果要在Vector容器中存放结构体类型的变量,经常见到两种存放方式.

方式一：放入这个结构体类型变量的副本。
方式二：放入指向这个结构体类型变量的指针。
假设结构体类型变量是这样的，

typedef struct student{   char school_name[100];   char gender;   int age;   bool is_absent;} StudentInfo;

那么，方式一和方式二的实现分别如下所示：

/*[方式一] 结构体放栈中,vector中放副本---------------------*/#include <iostream>#include <string>#include <vector>typedef struct student{   char school_name[100];   char gender;   int age;   bool is_absent;} StudentInfo; typedefstd::vector<StudentInfo> StudentInfoVec;void print(StudentInfoVec* stduentinfovec){   for (int j=0;j<(*stduentinfovec).size();j++)    {       std::cout<<           (*stduentinfovec)[j].school_name<<"\t"<<           (*stduentinfovec)[j].gender<<"\t"<<           (*stduentinfovec)[j].age<<"\t"<<           (*stduentinfovec)[j].is_absent<<"\t"<<std::endl;    }   return;} int main(){   StudentInfo micheal={"Micheal",'m',18,false};   StudentInfo cherry={"Cherry",'f',16,true};   StudentInfoVec studentinfovec;   studentinfovec.push_back(micheal);   studentinfovec.push_back(cherry);   print(&studentinfovec);   return 0;}

方式一的输出结果

/*[方式二]  结构体放入堆中，vector中放指针---------------------*/typedef struct student{   char* school_name;   char gender;   int age;   bool is_absent;} StudentInfo; typedefstd::vector<StudentInfo*> StudentInfoPtrVec;void print(StudentInfoPtrVec*stduentinfoptrvec){   for (int j=0;j<(*stduentinfoptrvec).size();j++)    {       std::cout<<           (*stduentinfoptrvec)[j]->school_name<<"\t"<<           (*stduentinfoptrvec)[j]->gender<<"\t"<<           (*stduentinfoptrvec)[j]->age<<"\t"<<           (*stduentinfoptrvec)[j]->is_absent<<"\t"<<std::endl;    }   return;}int main(){    StudentInfoPtrVec studentinfoptrvec;    char* p_char_1=NULL;   p_char_1=new char[100];   strcpy(p_char_1,"Micheal");   StudentInfo* p_student_1=new StudentInfo;   p_student_1->school_name=p_char_1;   p_student_1->gender='m';   p_student_1->age=18;   p_student_1->is_absent=false;   studentinfoptrvec.push_back(p_student_1);    char* p_char_2=NULL;   p_char_2=new char[100];   strcpy(p_char_2,"Cherry");   StudentInfo* p_student_2=new StudentInfo;    p_student_2->school_name=p_char_2;   p_student_2->gender='f';   p_student_2->age=16;   p_student_2->is_absent=false;   studentinfoptrvec.push_back(p_student_2);         print(&studentinfoptrvec);   delete p_char_1;   delete p_student_1;   delete p_char_2;   delete p_student_2;   return 0; }

方式二的输出结果，同上，依然是

类 结构体 使用实例

#include "stdafx.h"#include <vector>#include <string>using namespace std;class AClass{public:    int num;    string name;};struct AStruct {    int num;    string name;};void TestStruct(){ //类的使用    AClass Ac;    vector<AClass> vc;    Ac.num=10;    Ac.name="name";    vc.push_back(Ac);    AClass d;      for (vector<AClass>::iterator it=vc.begin();it<vc.end();++it)      {          d=*it;          cout<<d.num<<endl;     }  //结构体的使用    AStruct As;    vector<AStruct> vs;    As.num=10;    As.name="name";    vs.push_back(As);    AStruct ds;      for (vector<AStruct>::iterator it=vs.begin();it<vs.end();++it)      {          ds=*it;          cout<<ds.num<<endl;     } }void TestPoint(){ //类的使用    AClass *Ac=new AClass;    vector<AClass *> vc;    Ac->num=10;    Ac->name="name";    vc.push_back(Ac);    AClass *d;      for (vector<AClass*>::iterator it=vc.begin();it<vc.end();++it)      {          d=*it;          cout<<d->num<<endl;     } }int _tmain(int argc, _TCHAR* argv[]){    TestStruct();    TestPoint();    int n;    cin>>n;    return 0;} 

排序：

方法一：在结构体中重载<  、>运算符，调用STL的sort（）函数#include "stdafx.h"#include <vector>#include <algorithm>#include <iostream>using namespace std;class  MYSTRUCT{public:    int id;    int nums;    vector<int> vec;    MYSTRUCT()    {        id=numeric_limits<int>::max();        nums=0;        vec.resize(0);    }//重载==    bool operator==( const MYSTRUCT& objstruct) const    {        return objstruct.id==id;    }//重载<    bool operator<(const MYSTRUCT& objstruct) const    {        return id<objstruct.id;    }//重载>    bool operator>(const MYSTRUCT& objstuct) const    {        return id>objstuct.id;    }};int _tmain(int argc, _TCHAR* argv[]){    vector<MYSTRUCT> structs;    for(int i=0;i<9;i++)    {        MYSTRUCT myStruct;        //myStruct.id=i;        myStruct.nums=i;        structs.push_back(myStruct);    }    structs[0].id=9;    structs[1].id=1;    structs[2].id=7;    structs[3].id=3;    structs[4].id=8;    structs[5].id=2;    structs[6].id=6;    structs[7].id=0;    structs[8].id=10;    sort(structs.begin(),structs.end());    for(vector<MYSTRUCT>::iterator it=structs.begin();it!=structs.end();++it)    {        std::cout<<it->id<<endl;    }    return 0;}微笑方法二： 单独定义比较函数，调用STL的sort（）函数，不修改结构体#include "stdafx.h"#include <vector>#include <algorithm>#include <iostream>using namespace std;class  MYSTRUCT{public:    int id;    int nums;    vector<int> vec;    MYSTRUCT()    {        id=numeric_limits<int>::max();        nums=0;        vec.resize(0);    }// //重载==// bool operator==( const MYSTRUCT& objstruct) const// {// return objstruct.id==id;// }// // //重载<// bool operator<(const MYSTRUCT& objstruct) const// {// return id<objstruct.id;// }// // //重载>// bool operator>(const MYSTRUCT& objstuct) const// {// return id>objstuct.id;// }};    bool lessCompare(const MYSTRUCT& obj1,const MYSTRUCT&  obj2)    {        return obj1.id<obj2.id;    }    bool greaterCompare(const MYSTRUCT& obj1,const MYSTRUCT& obj2)    {        return obj1.id>obj2.id;    }    int _tmain(int argc, _TCHAR* argv[])    {        vector<MYSTRUCT> structs;        for(int i=0;i<9;i++)        {        MYSTRUCT myStruct;        //myStruct.id=i;        myStruct.nums=i;        structs.push_back(myStruct);    }    structs[0].id=9;      structs[1].id=1;    structs[2].id=7;    structs[3].id=3;    structs[4].id=8;    structs[5].id=2;    structs[6].id=6;    structs[7].id=0;    structs[8].id=10;    sort(structs.begin(),structs.end(),lessCompare);    for(vector<MYSTRUCT>::iterator it=structs.begin();it!=structs.end();++it)    {        std::cout<<it->id<<endl;    }    return 0;}

参考转自：

http://blog.csdn.net/feliciafay/article/details/9128385

http://blog.csdn.net/loveheronly/article/details/7900799

http://blog.csdn.net/tigernana/article/details/7293758