2d array and pointers in details

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1. int array[5][10];
2.  

Here array is the address of array[0]. Since array[0] is an array of 10 int, array is the address of an array of 10 int. You can assign the name array to a pointer to an array of 10 int:

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1. int array[5][10];
2.  
3. int (*ptr)[10] = array;
4.  

Fourth, when the number of elements is not known at compile time, you create the array dynamically:

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1. int* array = new int[value];
2. int (*ptr)[10] = new int[value][10];
3. int (*ptr)[10][15] = new int[value][10][15];
4.  

In each case value is the number of elements. Any other brackets only describe the elements.

Using an int** for an array of arrays is incorrect and produces wrong answers using pointer arithmetic. The compiler knows this so it won't compile this code:

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1. int** ptr = new int[value][10];    //ERROR
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new returns the address of an array of 10 int and that isn't the same as an int**.

Likewise:

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1. int*** ptr = new int[value][10][15];    //ERROR
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new returns the address of an array of 10 elements where each element is an array of 15 int and that isn't the same as an int***.