Function add exists that takes 4 arguments. The first 3 arguments are references to const int, the fourth argument is bool. The function returns pointer for int.
Function make_add_to takes 3 arguments. First is a pointer to function with the same structure as Add function, the second argument is a reference to const int, third is bool. This function returns a pointer to a function that takes a reference to const int and returns pointer for int.
add_to is a pointer to function, which is returned from function make_add_to
Can anyone finish this? I'm not sure if make_add_to is correct though
#include <iostream>
using namespace std;
int * add(const int &x1, const int &x2, const int &x3, bool y);
int * (*make_add_to(const int &x5))(int *(*f)(const int &x1, const int &x2, const int &x3, bool y),const int &x4, bool y);
int main()
{
int x=3,y=2,z=1;
//cout << *dodaj(x,y,z,true);
int *(*ptr)(const int &x1, const int &x2, const int &x3, bool y) = &add;
//cout << *ptr(x,y,z,true);
// (*dodaj_do)
}
int * add(const int &x1, const int &x2, const int &x3, bool y)
{
int * re = new int;
int x = x1+x2+x3;
re = &x;
return re;
}
This should work:
#include <iostream>
using namespace std;
int* add(const int &x1, const int &x2, const int &x3, bool y);
int* (*make_add_to(int*(const int&, const int&, const int&, bool),const int &x4, bool y))(const int&);
int main()
{
int x=3,y=2,z=1;
auto res_add = add(x,y,z,true);
cout << *res_add;
int* (*ptr)(const int &x1, const int &x2, const int &x3, bool y) = &add;
auto res_add_ptr = ptr(x,y,z,true);
cout << *res_add_ptr;
/* might leak memory before reaching here */
delete res_add;
delete res_add_ptr;
}
int * add(const int &x1, const int &x2, const int &x3, bool y)
{
int *re = new int{0};
*re += x1+x2+x3;
return re;
}
but you should use something like this
#include <iostream>
#include <memory>
std::unique_ptr<int> add(const int &x1, const int &x2, const int &x3, bool y);
auto make_add_to(std::unique_ptr<int>(const int&, const int&, const int&, bool),const int &x4, bool y);
int main()
{
int x=3,y=2,z=1;
std::cout << *add(x,y,z,true);
auto ptr = &add;
std::cout << *ptr(x,y,z,true);
}
std::unique_ptr<int> add(const int &x1, const int &x2, const int &x3, bool y)
{
auto re = std::make_unique<int>(0);
*re += x1+x2+x3;
return re;
}
Function
int * (*make_add_to(const int &x5))(int *(*f)(const int &x1, const int &x2, const int &x3, bool y),const int &x4, bool y);
is not used, and is not
make_add_to takes 3 arguments First is a pointer to function with the same structure as Add function, the second argument is a reference to const int, third is bool. This function returns a pointer to a function that takes a reference to const int and returns pointer to int
it's a pointer to function which takes 3 arguments...
and ask the question instead of ordering us to work finish something
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