PRODUCT  :  Borland C++                           NUMBER  :  1732
  VERSION  :  All
       OS  :  All
     DATE  :  October 25, 1993                         PAGE  :  1/2

    TITLE  :  Declaring a multi-dimensional array pointer




  /* NEWARAY.CPP - The declaration of a multi-dimensional array
     pointer

    "The operator new with arrays: If 'name' is an array, the
     pointer returned by 'new' points to the first element of the
     array. When creating multidimensional arrays with 'new', all
     array sizes must be supplied:

         mat_ptr = new int[3][10][[12];   // OK
         mat_ptr = new int[3[][12];       // illegal
         mat_ptr = new int[][10][12];     // illegal"

         pg 111, BC++ 2.0.d1 Programmer's Guide
         pg 109, BC++ 3.0.d1 Programmer's Guide
         pg 109, BC++ 3.1.d1 Programmer's Guide

     QUESTION: How is 'mat_ptr' declared?
  */

  #include <iostream.h>

  const dim1 = 10;
  const dim2 = 10;
  const dim3 = 10;

  // Global data is allocated from the default data segment
  int int_ptr1[dim1][dim2][dim3];

  //*************************************************************
  void main(void) {

    // local (automatic) data is allocated from the stack
    int int_ptr2[dim1][dim2][dim3];

    // Static data is allocated from the default data segment
    static int_ptr3[dim1][dim2][dim3];
    cout << endl << sizeof(int_ptr3);

    // First dimesnion is not specified...
    int (*int_ptr4)[dim2][dim3];

    // ...until we do the actual allocation. Dynamic allocations
    // are taken from the heap.













  PRODUCT  :  Borland C++                           NUMBER  :  1732
  VERSION  :  All
       OS  :  All
     DATE  :  October 25, 1993                         PAGE  :  2/2

    TITLE  :  Declaring a multi-dimensional array pointer




    int_ptr4 = new int [dim1][dim2][dim3];
    if (!int_ptr4)
      cout << "\nError allocating array 'int_ptr4'";

     int i, j, k;
     for (i=0; i<dim1; i++)
       for (j=0; j<dim2; j++)
         for (k=0; k<dim3; k++)
           int_ptr4[i][j][k] = i;

     for (i=0; i<dim1; i++)
       for (j=0; j<dim2; j++)
         for (k=0; k<dim3; k++)
           if (int_ptr4[i][j][k] != i)
             cout << "\nError in int_ptr4 array.";

    int (*int_ptr5)[dim2][dim3];
    int_ptr5 = new int [dim1][dim2][dim3];
    if (!int_ptr5)
      cout << "\nError allocating array 'int_ptr5'";

    for (i=0; i<dim1; i++)
      for (j=0; j<dim2; j++)
        for (k=0; k<dim3; k++)
          int_ptr5[i][j][k] = i;

    for (i=0; i<dim1; i++)
      for (j=0; j<dim2; j++)
        for (k=0; k<dim3; k++)
          if (int_ptr5[i][j][k] != i)
            cout << "\nError in int_ptr5 array.";

  } // end of main()


  DISCLAIMER: You have the right to use this technical information
  subject to the terms of the No-Nonsense License Statement that
  you received with the Borland product to which this information
  pertains.