sort instance

#include <iostream>#include <vector>#include <iterator>#include <algorithm>using namespace std;void print(vector<int>& vec){        vector<int>::iterator it;        for(it=vec.begin();it!=vec.end();it++)        {                cout << *it << "  ";        }        cout << endl;}bool funcom(int i, int j){        return i < j;}struct strcom{        bool operator()(int i, int j)        {                return i < j;        }}comobj;class clacom{public:        bool operator()(int i, int j)        {                return i < j;        }};int main(){        int arr[] = {10,46,25,68,78,78,2,45};        vector<int> vec(arr,arr+sizeof(arr)/sizeof(arr[0]));        print(vec);        sort(vec.begin(),vec.begin()+4);        print(vec);        sort(vec.begin()+4,vec.end(),funcom);        print(vec);        sort(vec.begin(),vec.end(),comobj);        print(vec);        sort(vec.begin(),vec.end(),clacom());        print(vec);        return 0;}