The following code example is taken from the book
The C++ Standard Library - A Tutorial and Reference, 2nd Edition
by Nicolai M. Josuttis, Addison Wesley Longman, 2012
Copyright © 2012 by Pearson Education, Inc. and Nicolai M. Josuttis
#include <unordered_set>
#include "print.hpp"
using namespace std;
int main()
{
// create and initialize, expand, and print unordered multiset
unordered_multiset<int> coll = { 1,2,3,5,7,11,13,17,19,77 };
coll.insert({-7,17,33,-11,17,19,1,13});
PRINT_ELEMENTS(coll);
// remove all elements with specific value
coll.erase(17);
// remove one of the elements with specific value
auto pos = coll.find(13);
if (pos != coll.end()) {
coll.erase(pos);
}
PRINT_ELEMENTS(coll);
}