[&] : capture by reference , all automatic storage duration variable declared in th reaching scope
[=] : capture by value, a value is copied
[x,&y] : capture x by value and y by a reference explicitly
[&] : capture by reference , all automatic storage duration variable declared in th reaching scope
[=] : capture by value, a value is copied
[x,&y] : capture x by value and y by a reference explicitly