Vector class - print out series of inverse numbers

#include < iostream>
#include < vector>
using namespace std;
int main() {
vector < int> v;
int n;

cout<<"Key in -1 to end the list of numbers"<< endl;
do {
cout << "=> ";
cin >> n;
if (n!=-1) v.push_back(n);
} while (n!=-1);// Enter -1 to exit

for (int i=0; i < v.size() ; i++)
cout << v[v.size()-i-1] << " "; // print out inverse list

}