排序有关问题 急

#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

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};
  vector<int> myvector (myints, myints+8);               // 32 71 12 45 26 80 53 33
  vector<int>::iterator it;

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

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

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

  // print out content:
  cout << "myvector contains:";
  for (it=myvector.begin(); it!=myvector.end(); ++it)
    cout << " " << *it;

  cout << endl;

  return 0;
}

------解决方案--------------------
重载个operator<

bool operator<(const Student& s1, const Student& s2)
{
   if (s1.a2 < s2.a2)
        return true;
   else
        return s1.a1 < s2.a1;
  //根据需要自己改
}
std::sort(sutVector.begin(), stuVector.end());

------解决方案--------------------

我在 VC6.0上没错啊

C/C++ code

#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;

struct stu
{
    int a1,a2,a3,a4;
};
bool cmp(stu a, stu b)
{
    if(a.a2 == b.a2)
        return a.a1 < b.a1;
    else
        return a.a2 < b.a2;
}
int main()
{
    vector<stu> v;
    stu st1,st2,st3;

    st1.a1= 3; st1.a2=4;st1.a3=5;st1.a4=6;
    v.push_back(st1);
    st2.a1= 2; st2.a2=4;st2.a3=5;st2.a4=6;
    v.push_back(st2);
    st3.a1= 1; st3.a2=4;st3.a3=5;st3.a4=6;
    v.push_back(st3);

    sort(v.begin(), v.end(), cmp);

    for(int i = 0; i<3; ++i)
    {
        cout<<v[i].a1<<" ";
    }
    cout<<endl;
    return 0;
}