C++中的结构体vector排序问题

// sort algorithm example
#include <iostream>     // std::cout
#include <algorithm>    // std::sort
#include <vector>       // std::vector

bool myfunction (int i,int j) { return (i<j); }

struct myclass {
  bool operator() (int i,int j) { return (i<j);}
} myobject;

int main () {
  int myints[] = {32,71,12,45,26,80,53,33};
  std::vector<int> myvector (myints, myints+8);               // 32 71 12 45 26 80 53 33

  // using default comparison (operator <):
  std::sort (myvector.begin(), myvector.begin()+4);           //(12 32 45 71)26 80 53 33

  // using function as comp
  std::sort (myvector.begin()+4, myvector.end(), myfunction); // 12 32 45 71(26 33 53 80)

  // using object as comp
  std::sort (myvector.begin(), myvector.end(), myobject);     //(12 26 32 33 45 53 71 80)

  // print out content:
  std::cout << "myvector contains:";
  for (std::vector<int>::iterator it=myvector.begin(); it!=myvector.end(); ++it)
    std::cout << ' ' << *it;
  std::cout << '\n';

  return 0;
}

#include "privateHeader.h"
#include <string>
#include <vector>
#include <iostream>
#include <algorithm>
using std::string;
using std::vector;
using std::cout;
using std::endl;
using namespace std;

typedef struct
{
    float score;
    string file_name;
    string all_file_name;

}TFileProp;

bool GreaterSort(TFileProp a, TFileProp b)
{
    return (a.score > b.score);
}
bool LessSort(TFileProp a, TFileProp b)
{
    return (a.score < b.score);
}
vector<TFileProp> VecFileProp;

VecFileProp.push_back(tFileProp);    //对vector进行push操作

std::sort(VecFileProp.begin(), VecFileProp.end(), GreaterSort);    //进行降序排序
std::sort(VecFileProp.begin(), VecFileProp.end(), LessSort);    //进行升序排序

int main(int argc, char** argv)
{
    // 统计时间
    //timeStatistics();

    // 所有结果放到一个文件夹显示

    int num_save;
    if (argc == 2)
    {
        std::string thres = argv[1];
        num_save = atof(thres.c_str());
        //std::cout << "(int)argv[1] is " << argv[1];
        //std::cout << "num_save is " << num_save;
    }
    else
    {
        num_save = 100;
    }
    showAllResult(num_save);


    return 1;
}

#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
typedef struct stu{
	int niD;
	string strName;
	bool operator < (stu const& a) const  {
		if(niD < a.niD) return true;
        if(niD == a.niD)
			return strName.compare(a.strName) < 0;
        return false;
    }
}stu;
bool cmp(stu a,stu b){
    if(a.niD > b.niD) return true;
    if(a.niD == b.niD)
        return a.strName.compare(b.strName) < 0;
    return false;
}
int main(){
    vector<stu> v;
    stu a;
    stu b;
    a.niD=1;
    a.strName="sfr";
    b.niD=0;
    b.strName="sfr1";
    v.push_back(a);
    v.push_back(b);
    for(stu s:v)
        cout<<s.niD<<endl;
    //结构体内重载小于号
    sort(v.begin(),v.end());
    for(stu s:v)
        cout<<s.niD<<endl;
    //使用cmp函数
    sort(v.begin(),v.end(),cmp);
    for(stu s:v)
        cout<<s.niD<<endl;
    return 0;
}