Class C++

[RytisBe]

Question: Your class should have functions called void setvalue(int index) and
int getvalue(int index) that allow you to set and get the value in the array
at a given index.

- I am not sure how to implement this one.. Can anyone please help me, thank you.

  class MyArray {

private:
	int N;
	int* ptr;

public:
	// default constructor
	MyArray() {
		ptr = NULL;
		N = 0;
		
		// deletes the array pointed to by "ptr"
		delete[] ptr;
	}
	// initialisation constructor
	MyArray(int n) {
		N = n;
		ptr = new int[N];	// dynamic memory allocation 
	}

	// destructor
	~MyArray() {
		delete ptr; // memory is released
	}

	// member functions
	int getVal(int i) {
		;
	}
	
	void setVal(int i) {
		;
	}

[RytisBe]

- I tried this, but i believe that it is not the way to do it.

	int getVal(int i) {
		return ptr[i];
	}
	
	void setVal(int i) {
		ptr[i];
	}

[JLBorges]

#include <cstddef>

class MyArray {

    private:
       
        // default member initialisers
        // http://www.stroustrup.com/C++11FAQ.html#member-init
        std::size_t size = 0 ;
        int* ptr = nullptr ;

    public:

        MyArray() = default ; // initialise using default member initialisers

        // http://en.cppreference.com/w/cpp/language/initializer_list
        MyArray( std::size_t n ) : size(n), ptr( new int[size]{} ) {} ;

        ~MyArray() { delete[] ptr ; } // *** note: delete[]

        // http://www.stroustrup.com/C++11FAQ.html#default
        MyArray( const MyArray& ) = delete ; // non-copyable
        MyArray& operator= ( const MyArray& ) = delete ; // non-assignable

        int getVal( std::size_t pos ) const {

            if( pos < size ) return ptr[pos] ;

            else /* error: pos is out of bounds */ return 0 ;
        }

        void setVal( std::size_t pos, int value ) {

            if( pos < size ) ptr[pos] = value ;
            else ; // error: pos is out of bounds: do nothing
        }
};