If the MyStruct type is implemented such that a deep copy is made upon initializing an MyStruct object with an object of the same type, what is the output of this program?

struct MyStruct $\{$

size$\_$t number;

char$*$ letter;

MyStruct$()=$ default;

MyStruct$($const MyStruct& source$)\{/*$ implementation hidden $*/\}$

$\}$;

int main$()\{$

MyStruct foo;

foo.number $=5$;

foo.letter $=$ new char$(\text{'}$z$\text{'})$;

MyStruct bar $=$ foo;

$*($bar$.$letter$)=\text{'}$b$\text{'}$;

std::cout $<<$ foo.letter $<<$ std::endl; $//$ What will this print?

$\}$