Passing Arrays as Function Arguments - objective C

If you want to pass a single- dimensional array as an argument in a function, you would have to declare function formal parameter in one of following three ways and all three declaration methods produce similar results because each tells the compiler that an integer pointer is going to be received. Similar way, you can pass multi-dimensional array as formal parameter.

Way 1
Formal parameters as a pointer as follows. 

- (void) mufuncion (int *)param
{
.
.
}

Way 2 

- (void) myfunction (int [10]) param 
{
.
.
}

Way 3 
Formal parameters as an unsized array as follows:

- (void) myfunction : ( int [] ) param 
{
.
.
}

Example 
Now consider the following function, which will take an array as argument along with another argument and based on the passed argument, it will return average of the numbers passed through the array as follows:

- (double) getaverage : (int []) arr andSixe : (int) size
{
   int i;
   double avg;
   double sum;
   for(i = 0; i<size; ++i)
   {
          sum += arr[i];
   }
   avg = sum / size;
   return avg;
}

Now let us call the above function as follows:

#import <Foundation/Foundation.h>

@interface SampleClass : NSObject 
          //function declaration
- (double) getAverage :(int []) arr andSize : (int) size;
@end

@implementation SampleClass

- (double) getAverage :(int []) arr andSize : (int) size
{
    int i;
    double avg;
    double sum = 0;
    for(  = 0; i<size; ++i)
    {
             sum = sum / size;
    return avg;
 }
 @end

int main()
{
     // an int array with 5 element
     int balance[5] = {1000, 2, 3, 17, 50};
     double avg;
     SampleClass obj = [SampleClass alloc]init];
                                                                             //pass pointer to the array as an argument
     avg = [obj getAverage:balance andSize: 5];
      
//output the returned value
  NSLog(@"Average value is :%f", avg);
   return 0;
}

As you can see, the length of the array doesn't matter as far as the function is concerned because objective C performs no bounds checking for the formal parameters.