#include<iostream>
#include<functional>
using namespace std;
class student
{
public:
int fun1(int m) {
return 2*m;
}
};
int main()
{
student s;
int l=5;
//int my=s.wrapper(&student::fun1(l));
int my=mem_fn(&student::fun1)(&s,l);
cout<<my<<endl;
return 0;
}
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