Queue in objective c

gistfile1.m

//
//  RRQueue.h
//  learnObjectiveC
//
//  Created by darshan on 3/19/15.
//  Copyright (c) 2015 Happy Days. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface RRQueue : NSObject
-(BOOL) isEmpty;
-(void) enQueue:(NSObject*)object;
-(NSObject*) deQueue;
@end


//
//  RRQueue.m
//  learnObjectiveC
//
//  Created by darshan on 3/19/15.
//  Copyright (c) 2015 Happy Days. All rights reserved.
//

#import "RRQueue.h"

@interface RRQueue()
@property (nonatomic, strong) NSMutableArray *array;
@end

@implementation RRQueue
-(id) init {
    if (self) {
        // initialize this for maintaining the queue
        self.array = [NSMutableArray new];
    }
    return self;
}
-(BOOL)isEmpty {
    if ([self.array count] > 0) {
        return NO;
    }
    return YES;
}
-(void)enQueue:(NSObject *)object {
    [self.array addObject:object];
}
-(NSObject *)deQueue {
    if ([self.array count] > 0) {
        NSObject *firstObject = [self.array firstObject];
        [self.array removeObjectAtIndex:0];
        return firstObject;
    }
    return nil;
}
@end