### 3D array not working

Im trying to store multiplication in a 3D array allocated through pointers (a practice problem in a book). I can get the 3D array but I cant store the multiplication in the pointer array (i guess you can say) in the for loop of the function "three dimensional array" any ideas why? When i comment out the whole for loop it works fine.

 ``12345678910111213141516171819202122232425262728293031323334353637383940`` ``````#include using namespace std; /** Function that makes a three dimensional array with its argurment using a pointer and multiplies numbers in a loop for its values and stores it in the array of pointers **/ void ***three_dimensional_array (int ***arg1) { for (int i = 0; i < 9; ++i) { arg1[i] = new int*[9]; } for (int i = 0; i < 9; ++i) { for (int j = 0; j < 9; ++j) { for (int k = 0; k < 9; ++k) { arg1[i][j][k] = i * j * k; // stores multiplication in 3DI ARRAY cout << arg1[i][j][k] << '\t'; } } } delete[] arg1; } // call the function in main int main() { int ***three_p_free_store = new int**[9]; three_dimensional_array(three_p_free_store); }``````
Where is arg1[i][j][k] pointing?
Your array shall have i * j * k ( 9 * 9 * 9 ) elements.
You allocated only i * j ( 9 * 9 ) elements. The firs i ( 9 ) elements you allocated with the statement

int ***three_p_free_store = new int**[9];

and the next j ( 9 ) elements for each i you allocated with the statement

for (int i = 0; i < 9; ++i)
{
arg1[i] = new int*[9];
}

So now you need to allocate the next k ( 9 ) elements for each i * j.

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 a practice problem in a book

What kind of book would that be? What i'd be hoping to see in a C++ book would be "here you have C-style arrays. They exist. Now let's move on to std::vector and std::array)". If you have 2 dimensional C style arrays in your code, something is fishy. If you get to 3, something is very, very wrong in your code.

 hanst99 (2757) Now let's move on to std::vector and std::array)".

Now it is very interesting to me. I would like to know did you use std::array with multidimensional arrrays?!:) Tell us how std::array is convient to use with multidimensional arrrays.:)
If the dimensions are fixed std::array works fine as multidimensional array.

`std::array<std::array<std::array<int, 9>, 9>, 9> three_dimensional_array;`

@Peter87
 If the dimensions are fixed std::array works fine as multidimensional array. std::array, 9>, 9> three_dimensional_array;

It is not a working with multidimensional array. It is a declaration from which it is not clear which subscriptor is the first, which is the second and so on. Show for example a construction with std::array that corresponds to alement record of a usual array as

a[1][2][3];
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sorry i couldnt reply sooner, the website was down. thanks for all your help. Vlad From Moscow, your idea worked and now the array is able to be used. Thank you.
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