How to print the elements of an array of structures?

Question

I am new to c++ , I was trying to print the fields of a structure using an array.

I know the compiler is not able to understand what is inside deck[1] in the line for(int x:deck[1]), since deck[1] is an unknown data type (a structure datatype defined as 'card'). So x is not able to scan the elements within this data type.

I wish to know, how may I print the elements within this deck[1], i.e {1,1,1}.

#include <iostream>
using namespace std;

struct card
{
    int face;
    int shape;
    int color;
};

int main()
{
    
    struct card deck[52];
    
    deck[1].face=1;
    deck[1].shape=1;
    deck[1].color=1;
    
    cout<< sizeof(deck)<<endl;
    
    for(int x:deck[1])
    {
        cout<<x<<endl
    }

    return 0;
}

Answer 1

Note that you can't loop through the data members of an object of a class type such as card. You can only print out the data members individually. So you can use operator overloading to achieve the desired effect. In particular, you can overload operator<< as shown below.

#include <iostream>

struct card
{
    int face;
    int shape;
    int color;
    
    //overload operator<<
    friend std::ostream& operator<<(std::ostream &os, const card& obj);
};

std::ostream& operator<<(std::ostream &os, const card& obj)
{
    os << obj.face << " " << obj.shape << " " << obj.color;
    return os;
}

int main()
{ 
    card deck[52] = {};
    
    deck[1].face = 1;
    deck[1].shape = 1;
    deck[1].color = 1;
    
    std::cout << deck[1].face << " " << deck[1].shape << " " << deck[1].color << std::endl;
    
    //use overloaded operator<<
    std::cout << deck[1] << std::endl;\
}

The output of the above program can be seen here:

1 1 1
1 1 1