lst-0094-book.cpp
// https://godbolt.org/z/8948besY8
map<string,string> data { {"John","Wayne"}, {"Cary","Grant" }, };
cout <<= data; // Cary:Grant John:Wayne
data.rbegin()->second = "Travolta"; // Overwrite target
cout <<= data; // Cary:Grant John:Travolta