c++ - New to pointers, what's the difference between these? -

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• what differences between pointer variable , reference variable in c++? 30 answers

both of these functions rewrites original value right? there benefit doing 1 way on other?

#include <iostream> using namespace std;  void passptr(int *p) {     *p = 7; }  void passaddy(int &a) {     = 7; }  int main() {     int = 5;     int *p = &a;      passptr(p);     cout << << endl;      = 5;     passaddy(a);     cout << << endl;      return 0; } 

in case, references superior because cannot make common mistakes of pointers--references must point type of object reference, , cannot ever null or nullptr, automatically eliminates many of headaches of dealing pointers.

some compilers can use pointers implement references, 2 have different semantics. these semantics useful in different cases. here, it's easier not have remember dereference pointer--it's pesky layer of abstraction won't trip on when code. in other cases, might favourable able have null pointer or reference.