如何使用智能指针声明二维数组？

Question

unique_ptr<int> ptr1(new int {});
unique_ptr<int[]> ptr2(new int[5] {});

单个和一维数组可以像上面那样声明。如何声明一个二维或多维数组为智能指针？

const size_t idx = 5;
// 2D
int** ptr3 = new int*[idx]{};
for (size_t i = 0; i < idx; i++)
{
    ptr3[i] = new int[idx]{};
}
for (size_t i = 0; i < idx; i++)
{
    delete[] ptr3[i];
}
delete[] ptr3;


// 3D
int*** ptr4 = new int**[idx]{};
for (size_t i = 0; i < idx; i++)
{
    ptr4[i] = new int*[idx]{};
    for (size_t j = 0; j < idx; j++)
    {
        ptr4[i][j] = new int[idx]{};
    }
}
... skip ...

-----> smart pointer version?

Answer 1

可能这就是您要找的东西，但我认为它不实用。您可以改用向量的向量或某种可以处理多维数组的其他结构或库。

int main()
{
    unique_ptr<unique_ptr<int[]>[]> ptr(new unique_ptr<int[]>[5] {});

    for (int i = 0; i < 5; i++)
    {
        unique_ptr<int[]> temp_ptr(new int[5]);
        for (int j = 0; j < 5; j++)
            temp_ptr[j] = i*5 + j;
        ptr[i] = move(temp_ptr);
    }


     for (int i = 0; i < 5; i++)
     {
         for (int j = 0; j < 5; j++)
            cout << ptr[i][j] << " ";
        cout << "\n";
     }
}

如何使用智能指针声明二维数组？

How to declare an array over two dimensions with smart pointers?

c++

arrays

smart-pointers