functional filter()

 #include "pch.h"
 #include <iostream>
 #include <deque>
 #include <string>
 #include <list>
 #include <algorithm>
 #include <vector>
 #include <functional>
 using namespace std;

 template<typename InputIterator, typename OutputIterator,typename ElemType, typename Comp>
 OutputIterator
 filter(InputIterator first, InputIterator last, 
　　　　　　OutputIterator at, const ElemType &val, Comp pred)
 {
     while((first=find_if(first, last, bind2nd(pred, val)))!=last)
     {
         cout << "found value:" << *first << endl;
         *at++ = *first++;
     }
     return at;
 }

 int main()
 {
     const int elem_size = ;
     int ia[elem_size] = { ,,,,,,, };
     vector<int> ivec(ia,ia+elem_size);
     int ia2[elem_size];
     vector<int> ivec2(elem_size);
     cout << "filtering integer array for values less than 8\n";
     filter(ia, ia + elem_size, ia2, elem_size, less<int>());
     cout << "filtering integer vector for values greater than 8\n";
     filter(ivec.begin(), ivec.end(), ivec2.begin(), elem_size, greater<int>());
     return ;
 }