lst-0018-book.cpp
// https://godbolt.org/z/MszTjE3dv
const regex pattern{R"(^score)"
R"(\s+)"
R"((\d+))" // points
R"(\s+)"
R"(for)"
R"(\s+)"
R"((\d+))" // number of nights
R"(\s+)"
R"(night)"
R"(s?)" // optional: plural
R"(\s+)"
R"(at)"
R"(\s+)"
R"((.*))" // hotel name
R"()"};