The following code example is taken from the book
The C++ Standard Library - A Tutorial and Reference
by Nicolai M. Josuttis, Addison-Wesley, 1999
© Copyright Nicolai M. Josuttis 1999
#include <iostream>
#include <set>
using namespace std;
int main ()
{
set<int> c;
c.insert(1);
c.insert(2);
c.insert(4);
c.insert(5);
c.insert(6);
cout << "lower_bound(3): " << *c.lower_bound(3) << endl;
cout << "upper_bound(3): " << *c.upper_bound(3) << endl;
cout << "equal_range(3): " << *c.equal_range(3).first << " "
<< *c.equal_range(3).second << endl;
cout << endl;
cout << "lower_bound(5): " << *c.lower_bound(5) << endl;
cout << "upper_bound(5): " << *c.upper_bound(5) << endl;
cout << "equal_range(5): " << *c.equal_range(5).first << " "
<< *c.equal_range(5).second << endl;
}