C - function declearation

**alenscrist** · 01-20-2010 12:11 PM

Hi Guys,

I have written the program for accesssing elements of 2D array using pointer to array of int which is as below:

void display(int (*)[4], int , int);

int main()
{
int a[2][4] = {{1,2,3,4},
{5,6,7,8}
};

display(a, 2, 4); // this line is giving error

getch();
}

void display(int (*ptr)[4], int row, int col)
{

int i, j;
int *p;

for(i = 0; i < row; i++)
{
p = ptr + i;
for( j= 0; j < col; j++)
{
printf("%d ", *(p+j));
}
printf("\n");
}
}

But the function declearion line is giving the error and also I am not sure about function prototype written correct or not.

Please help me in how the function prototype and declearation has to be written for the above fucntion defination.

Thanks

**cools4u** · 03-29-2010 10:18 AM

Hi, I have mentioned below some changes u can do to run the code successfully :

1. Change the prototype of the function

from : [COLOR=Red]void display(int (*)[4], int , int);[/COLOR]

to : [COLOR=Blue]void display(int *, int , int);[/COLOR]

since u r sending the base address of the integer 2d array which will be catched by the integer pointer then no need to specify size in the function prototype...

2. If u r not returning any value as it seems the coding u have done for function main() then change it

from : [COLOR=Red]int main()[/COLOR]

to : [COLOR=Blue]void main()[/COLOR]

otherwise it will give a warning message.

3. In function display() change the code
from : [COLOR=Red]p = ptr + i;[/COLOR]

to : [COLOR=Blue]p = *(ptr + i);[/COLOR]

Make the above changes n u will get the result properly...if u have any further queries pl mention...