function - C++ Basic concept regarding reference operator return type -


i need clear basic concept. code works fine. can explain me if function caldouble returning address (reference) of int why need use & operator further in main int *j = &caldouble(i); address (reference) of int? thanks.

int& caldouble(int x) { x = x*2; return x; } int main(int argc, char *argv[]) { int = 99; int *j = &caldouble(i); system("pause"); return exit_success; }

int& caldouble(int x) doesn't return address, reference int.

you need take address of reference able assign pointer.

note code invokes undefined behavior. because pass parameter value, copy of created inside function. return local variable reference, not legal.

i think confusion comes &. can used in 2 ways:

  • applied variable &x, takes address
  • when in declaration int& x, defines reference

a reference alias, different name variable.

int x = 0; int& y = x;

now, x , y refer same variable.

int* z = &x;

takes address of x.


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