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develop dynamic buffer/memory

amitk3553 (102)

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unsigned int* buffer;
buffer = new() unsigned int[24];


I want to access 24 locations as 3 arrays of 8 bytes

Like want pointer to point on 0th, 8th, and 16th locations and respective 8 locations in each case 0-7, 8-15, 16-23 array accessed.

I want to use some concept like pointer of arrays and dynamically allocate memory for all.
Duthomhas (13206)
Use typedefs to help.
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#include <iomanip>
#include <iostream>
using namespace std;

int main()
  {
  // It is convenient to use typedefs to simplify your complex array type
  // (Sometimes it is necessary, but it isn't in this case.)
  typedef unsigned char byte;
  typedef byte eight_bytes[ 8 ];
  
  // Here's our prototype in the nice, easy-to-read way (using our typedefs)
  void print( eight_bytes*, unsigned );
  
  // Here we get our data from the heap
  // (But you could get it from anywhere, I guess...)
  eight_bytes* three_of_eight = new eight_bytes[ 3 ];

  // Lets set the array to be filled with numbers of the form: i 0 j
  for (unsigned i = 0; i < 3; i++)
  for (unsigned j = 0; j < 8; j++)
    three_of_eight[ i ][ j ] = i*100 + j;

  // Elephant, duh.
  print( three_of_eight, 3 );
  
  // Don't forget to clean up
  delete [] three_of_eight;

  return 0;
  }

// Here's our function without the nice, fancy typedefs to make life pretty
void print( unsigned char a[][ 8 ], unsigned size )
  {
  cout << setfill( '0' );
  for (unsigned n = 0; n < size; n++)
    {
    for (unsigned m = 0; m < 8; m++)
      cout << setw( 3 ) << (int) a[ n ][ m ] << " ";
    cout << "\n";
    }
  }
 
000 001 002 003 004 005 006 007
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Remember, the pointer on line 17 need not be aimed at memory on the heap. You could easily aim it at something simple, like a flat (1D) array with your data, or whatever it is you want to access the bytes of.

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                  //012345670123456701234567
  char message[] = "Earth laughs in flowers.";
  
  three_of_eight = (eight_bytes*)message;
  
  print( three_of_eight, 3 );

  return 0;
}
 
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117 103 104 115 032 105 110 032
102 108 111 119 101 114 115 046


Hope this helps.
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