NSArray

gistfile1.txt

#import <Foundation/Foundation.h>
#import "BNRStockHolding.h"

@interface BNRPortfolio : NSObject
// Declaring Instance Variables

@property (nonatomic) NSMutableArray *stockHoldings;

// Declaring Methods


@end


Inside main: 

        // Setting up A portfolio
        BNRPortfolio *myPortfolio = [[BNRPortfolio alloc] init];
        [myPortfolio._stockHoldings addObject:instanceA];
        [myPortfolio._stockHoldings addObject:instanceB];