Исправить код с добавлением в плейлист

@interface Playlist : NSObject
@property (strong, nonatomic) NSString *masterLibName;
@property (strong, nonatomic) NSString *playlistName;
@property (strong, nonatomic) NSMutableArray *arrayPlaylist;
@property (strong, nonatomic) NSMutableArray *masterLibriary;
 
-(void) addSongToPlaylist: (Song *) s;
-(id) initPlaylistWithName: (NSString *) name;
-(id) initMasterLibriaryWithName: (NSString*) name;
@end
 
@implementation Playlist
@synthesize masterLibName, playlistName;
@synthesize arrayPlaylist, masterLibriary;
 
-(id) initMasterLibriaryWithName:(NSString *)name{
    self = [super init];
    if (self) {
        masterLibName = [NSString stringWithString: name];
        masterLibriary  = [NSMutableArray array];
    }
    return self;
}
 
-(id) initPlaylistWithName: (NSString *) name{
    self = [super init];
    if (self) {
        playlistName = [NSString stringWithString: name];
        arrayPlaylist = [NSMutableArray array];
    }
    return self;
}
 
-(instancetype) init{                                           
    return [self initPlaylistWithName:@"NOName"];
}
 
-(void) addSongToPlaylist: (Song*) s{
    [masterLibriary addObject: s];
    [arrayPlaylist addObject:s];
 
 
int main(int argc, const char * argv[]) {
    @autoreleasepool {
        Playlist * playlist1 = [[Playlist alloc] initPlaylistWithName:@"First playlist"];
        Playlist * playlist2 = [[Playlist alloc] initPlaylistWithName:@"Second playlist"];
        Playlist * playlist3 = [[Playlist alloc] initPlaylistWithName:@"Third playlist"];
        
        Playlist *masterLibCollection = [[Playlist alloc] initMasterLibriaryWithName:@"Master Libriary"];
 
        [playlist1 addSongToPlaylist:s1];
        [playlist2 addSongToPlaylist:s2]; [playlist2 addSongToPlaylist:s3];
        [playlist3 addSongToPlaylist:s4]; [playlist3 addSongToPlaylist:s5]; [playlist3 addSongToPlaylist:s6];
}
@end