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Passing Arrays

To pass an array , specify the name of the array without any brackets.
For a function to receive an array , the function's parameter list must specify that an array will be received.
In 2 dim array you must mention at least the column size of the array.
In General , the first subscript of a multiple-subscripted array is not required , but all subsequent subscripts are required.
All array elements are stored consecutively in memory regardless of the number of subscripts.

Pass	Function Call	Function	Prototype	What it passed ?
array elements	int g[5]; findMin(g[2],g[4]);	findMin(int g1,int g2);	findMin(int ,int );	copy of the passed value (pass by value)
complete array	average (g); // NO []	average (int g[]); OR average (int g[5]); average (int g);//WRONG	average (int []); OR average (int g[]);	actual array (pointer to the array , address of the first element in the array.)(pass by reference).
2 dim array	int t[3][4]; calc (t) ;	calc (t[][4]); OR calc (t[3][4]); calc (t[][]); //WRONG	calc (int t[][4]); OR calc (int t[3][4]); calc (t[][]) //WRONG

Address

The name of an array is the same as the address of the array's first element.

#include <stdio.h>

int main()
{
char array[ 5 ];

printf( " array = %p\n&array[0] = %p\n"
" &array = %p\n",
array, &array[ 0 ], &array );
return 0;
}

Output:

array = 0012FF64

&array[0] = 0012FF64

&array = 0012FF64

Why when we pass a complete array , the actual array is being passed not a copy of it ?

Because in large arrays making duplicate copies of the array for each function call would :

Waste computer storage.
Consume execution time.

const

The type qualifier const prevent modification of array values in a function.
When an array parameter is preceded by the const qualifier , the elements of the array become constant in the function body and any attempt to modify an element of the array in the function body results in compile time error.

#include <stdio.h>

void tryToModifyArray( const int [] );

int main()
{
int a[] = { 10, 20, 30 };

tryToModifyArray( a );
printf("%d %d %d\n", a[ 0 ], a[ 1 ], a[ 2 ] );
return 0;
}

void tryToModifyArray( const int b[] )
{
b[ 0 ] /= 2; /* error */
b[ 1 ] /= 2; /* error */
b[ 2 ] /= 2; /* error */
}