If I have a vector which has many duplicate elements,then I construct a set from this vector .

```
#include <iostream>
#include <set>
#include <vector>
using namespace std;
int main ()
{
    vector<pair<int,int> > myvec={{1,1},{1,2},{1,3},{2,1},{2,2},{2,3},{3,1},{3,2},{3,3}};
    auto comp=[](pair<int,int> a,pair<int,int> b){return a.first<b.first;};
    set<pair<int,int>, decltype(comp)> myset(myvec.begin(),myvec.end(),comp);
    for (auto p:myset)
        cout<<p.second<<endl;
    return 0;
}

```

My question is, is it guaranteed that these elements will be insert to the set by the order of the vector ,like :

```
for (auto p:myvec)
myset.insert(p);

```