cin/coutへのvectorの入出力

vecin.cpp

#include <bits/stdc++.h>
using namespace std;
 
template<typename T>
ostream& operator << (ostream& s, const vector<T>& v){
    int len = v.size();
    for (int i = 0; i < len; ++i){
        s << v[i]; if (i < len - 1) s << " ";
    }
    return s;
}
template<typename T>
istream& operator >> (istream& s, vector<T>& v){
    for(auto &x: v)
        s >> x;
    return s;
}
 
int main(){
    vector<int> vec(5);
    cin >> vec;
    cout << vec << endl;
    return 0;
}