Mixing C problems....

Can anyone please elaborate the meaning of "Macro in c "???
is that same one which is in excel??
one line meaning of macro pls...
and yes another thing...
a working program of Multidimensional array..( more than three or four pls..)
thanks...

 

I don't really know the science behind the macro, but they can be used to streamline tasks; You can do quite a bit with them, but they're also sneaky if you're not careful with them.

A basic example might be to print the ascii character along with its dec, oct, and hex values.

Code:

#include <stdio.h>
#include <ctype.h>

#define MYPRINT(x) \
   if(isprint(x)) \
      printf("ASCII %c; DEC %d; OCT %o HEX %x\n", (x),(x),(x),(x))

int main(void)
{
   int i;

   for(i=0; i < 128; ++i)
      MYPRINT(i);

   getchar();

   return 0;
}

for the 2d array, they're no different from a single dimension really. You've got the number of rows and a number of columns in each row.

Code:

int arr[5][5]; // 2d array with 5 rows and 5 cols

row 0; col 0-4

arr[0][0] = 0;
arr[0][1] = 0;
arr[0][2] = 0;
arr[0][3] = 0;
arr[0][4] = 0;

row 1; col 0-4

arr[1][0] = 1;
arr[1][1] = 1;
arr[1][2] = 1;
arr[1][3] = 1;
arr[1][4] = 1;

...

for(row=0; row < max_row; ++row)
{
   for(col=0; col < max_col; ++col)
      // do something some_2d_array[row][col]
}

// maybe read values into the array


int row, col, some_2d_array[3][5];

for(row=0; row < 3; ++row)
{
   for(col=0; col < 5; ++col)
      scanf("%d", &some_2d_array[row][col]);
}

Don't let extra dimensions confuse you; this bit is really no different than a set of single dimension arrays capable of holding 3, 4, 5, and 6 elements individually.

Code:

arr[3][4][5][6];

arr[0-2][0-3][0-4][0-5]

arr[1st][2nd][3rd][4th]

for(1st = 0 through 2)
   for(2nd = 0 through 3)
      for(3rd = 0 through 4)
         for(4th = 0 through 5)
             arr[1st][2nd][3rd][4th] = some_value;