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_map>
#include <string>
#include <iostream>
using namespace std;
int main()
{
unordered_map<string,double> coll { { "tim", 9.9 },
{ "struppi", 11.77 }
};
// square the value of each element:
for (pair<const string,double>& elem : coll) {
elem.second *= elem.second;
}
// print each element (key and value):
for (const auto& elem : coll) {
cout << elem.first << ": " << elem.second << endl;
}
}