lst-0042-book.cpp
// https://godbolt.org/z/PebG9bn9K
set<Dwarf,ByYear> dwarves2{begin(dwarves), end(dwarves)};
for(const auto& z : dwarves2) // differently sorted output
cout << z.year_ << " ";
// https://godbolt.org/z/PebG9bn9K
set<Dwarf,ByYear> dwarves2{begin(dwarves), end(dwarves)};
for(const auto& z : dwarves2) // differently sorted output
cout << z.year_ << " ";