stl 對vector存對象

#include <iostream>
#include <functional>
#include <iterator>
#include <vector>
#include <algorithm>

using namespace std;
class fun1{
 int a;
 int b;
 public:
  fun1(int x,int y):a(x),b(y){}
  int get_x(){return a;}
  int get_y(){return b;}
  void show(){cout<<"a: "<<a<<"b: "<<b<<endl;}
};
bool comp(fun1 &a)
{
    if((a.get_x()==2)&&(a.get_y()==3))
    return true;
    else return false;
}

int main()
{
    vector<fun1>coll;vector<fun1>coll2;
    coll.push_back(fun1(2,3));
    coll.push_back(fun1(12,23));
    coll.push_back(fun1(23,22));
    int num=count_if(coll.begin(),coll.end(),comp);

    for_each(coll.begin(),coll.end(),mem_fun_ref(&fun1::show));

return 0;

}