Different methods of passing Structures to Functions

fun_structures.cpp

#include <iostream>
using namespace std;

struct Queue{
  int size;
  int rear;
  int front;
};

void passing_pointer(struct Queue *p){
  cout << p->size << " ";
  cout << p->rear << " ";
  cout << p->front << " ";
}

void passing_struct(struct Queue p){
  cout << p.size << " ";
  cout << p.rear << " ";
  cout << p.front << " ";
}

int main(){
  struct Queue q;       // q is a Structure Object
  q.size = 10;
  q.rear = 20;
  q.front = 30;
  passing_pointer(&q);    // Passing the address (Call by address)
  cout << endl;
  passing_struct(q);      // Passing the value (Call by value)
}