#include<iostream>

using namespace std;

class Sample

{

    int data;

    public:

        Sample():data(0){}

        void TestFun(Sample s)

        {

            cout<<s.data;   //public data is accessible insde the class

        }

};

void TestFun(Sample s)

{

   // cout<<s.data;  //Won't be able to access public data outside the class

}

int main()

{

    Sample s;

    s.TestFun(s);

    TestFun(s);

}

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