How to Avoid Memory Issues When Dynamically Allocating an Array of Objects in C ?

Allocating an Array of Objects Dynamically

When working with objects that contain dynamically allocated arrays, creating an entire array of these objects can present challenges. Using a simple approach like:

A* arrayOfAs = new A[5];
for (int i = 0; i <p>leads to memory issues as the A objects destructed within the loop delete their internal myArray arrays, rendering the array elements of arrayOfAs invalid.</p><p>To avoid these issues, understanding the "rule of 4" (or the extended "rule of 5" in C  11) is crucial for classes containing raw pointers:</p><ol>
<li>Constructor</li>
<li>Destructor</li>
<li>Copy Constructor</li>
<li>Assignment Operator</li>
<li>Move Constructor (C  11)</li>
<li>Move Assignment (C  11)</li>
</ol><p>If not defined, the compiler generates its own versions of these methods, which may not be suitable for raw pointers.</p><p>To resolve the aforementioned error, the minimum requirements for a class containing a pointer to an array include:</p><pre class="brush:php;toolbar:false">class A {
    size_t mSize;
    int* mArray;
public:
    A(size_t s = 0) {mSize=s;mArray = new int[mSize];}
    ~A() {delete [] mArray;}

    A(A const& copy) {
        mSize = copy.mSize;
        mArray = new int[copy.mSize];
        // Handle copying of integers/other members
    }

    A& operator=(A other) {
        std::swap(mArray, other.mArray);
        std::swap(mSize, other.mSize);
        return *this;
    }
};

Alternatively, using standard containers like std::vector can simplify the process, as they handle memory management automatically:

class A {
    std::vector<int> mArray;
public:
    A(){}
    A(size_t s) :mArray(s)  {}
};</int>

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