2D Array Question

[jmsrickland]

I don't understand the array at the bottom of the code. It shows it as a 2d array 2 x 2 yet there are 16 members in it.

#define coMAX 2

#define isqB1 1
#define isqC1 2
#define isqD1 3
#define isqF1 5
#define isqG1 6
#define isqB8 113
#define isqC8 114
#define isqD8 115
#define isqF8 117
#define isqG8 118
		
#define cfE1G1	0x0001
#define cfE1C1	0x0002
#define cfE8G8	0x0004
#define cfE8C8	0x0008

typedef struct tagCSTL
{
  int cf;                    
  int isqRookTo;      
  int isqKnight;      
  int isqKingTo;      
}
CSTL;

CSTL const c_argcstl[coMAX][2] =
{
  cfE1G1,   isqF1,  isqG1,  isqG1,
  cfE1C1,   isqD1,  isqB1,  isqC1,
  cfE8G8,   isqF8,  isqG8,  isqG8,
  cfE8C8,   isqD8,  isqB8,  isqC8,
};

[Milk]

The array is 2 x 2 however each array element has 4 integer members.

CSTL const c_argcstl[coMAX][2] =
{
  // cf    RookTo  Knight  KingTo
  cfE1G1,  isqF1,  isqG1,  isqG1,
  cfE1C1,  isqD1,  isqB1,  isqC1,
  cfE8G8,  isqF8,  isqG8,  isqG8,
  cfE8C8,  isqD8,  isqB8,  isqC8,
};

[jmsrickland]

Not sure I completely understand. Is it like arrays within an array? How do I index isqG8 under the Knight column for example?

CSTL const c_argcstl[coMAX][2] =
{
 // cf    Rook To  Knight  KingTo
  cfE1G1,  isqF1,  isqG1,  isqG1,
  cfE1C1,  isqD1,  isqB1,  isqC1,
  cfE8G8,  isqF8,  isqG8,  isqG8,
  cfE8C8,  isqD8,  isqB8,  isqC8,
};

[Milk]

isqG8 would be indexed c_argcstl[1][0].isqKnight;

c_argcstl is an array of arrays of CSTL structures. The initializer goes in order [0][0], [0][1], [1][0], [1][1]

CSTL const c_argcstl[coMAX][2] =
{ // cf    RookTo  Knight  KingTo
  cfE1G1,  isqF1,  isqG1,  isqG1, //[0][0]
  cfE1C1,  isqD1,  isqB1,  isqC1, //[0][1]
  cfE8G8,  isqF8,  isqG8,  isqG8, //[1][0]
  cfE8C8,  isqD8,  isqB8,  isqC8, //[1][1]
};

[jmsrickland]

OK, I understand now. Thanks, Milk