Implicit declaration of function '...' is invalid on C99

#import "CIAViewController.h"

@interface CIAViewController()


@end

@implementation CIAViewController




-(IBAction)press {
cruzia.hidden = 0;
textarea.hidden = 0;
playbtn.hidden = 1;
tutorialbtn.hidden = 1;
optionsbtn.hidden = 1;
trainingbtn.hidden = 1;
back.hidden = 0;
cruzia.text = @"Play";
textarea.text = @"Hello! You are playing the game of Cruzia!";

    // declare defaults it is not declared elsewhere within your view controller
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];

    // The stringForKey method returns a String and not a Boolean value
    // However, if you just want to check if a value exists then it is implied you are checking for existence
    // If there is no value then it will return nil and statement will fail
    // You had "== YES" outside of the parenthesis which is an illegal statement
    if ([defaults stringForKey:kMusic])  {
        CFBundleRef mainBundle = CFBundleGetMainBundle();
        CFURLRef soundFileURLRef;
        soundFileURLRef =CFBundleCopyResourceURL(mainBundle, (CFStringRef) @"click",                     CFSTR ("wav"), NULL);
        UInt32 soundID;
        AudioServicesCreateSystemSoundID(soundFileURLRef, &soundID);
        AudioServicesPlaySystemSound(soundID); }

}


-(IBAction)press2 {
cruzia.hidden = 0;
textarea.hidden = 0;
playbtn.hidden = 1;
tutorialbtn.hidden = 1;
optionsbtn.hidden = 1;
trainingbtn.hidden = 1;
back.hidden = 0;
cruzia.text = @"Tutorial";
textarea.text = @"Welcome! You are watching the Cruzia tutorial!";
// declare defaults it is not declared elsewhere within your view controller
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];

// The stringForKey method returns a String and not a Boolean value
// However, if you just want to check if a value exists then it is implied you are checking for existence
// If there is no value then it will return nil and statement will fail
// You had "== YES" outside of the parenthesis which is an illegal statement
if ([defaults stringForKey:kMusic])  {
    CFBundleRef mainBundle = CFBundleGetMainBundle();
    CFURLRef soundFileURLRef;
    soundFileURLRef =CFBundleCopyResourceURL(mainBundle, (CFStringRef) @"click",                     CFSTR ("WAV"), NULL);
    UInt32 soundID;
    AudioServicesCreateSystemSoundID(soundFileURLRef, &soundID);
    AudioServicesPlaySystemSound(soundID); }
}

-(IBAction)press3 {
cruzia.hidden = 0;
textarea.hidden = 0;
playbtn.hidden = 1;
tutorialbtn.hidden = 1;
optionsbtn.hidden = 1;
trainingbtn.hidden = 1;
back.hidden = 0;
cruzia.text = @"Options";
textarea.text = @"Hello! You have clicked Options. Sadly, you need to open Settngs and go to the Cruzia area to get most of the options of the game.";
CFBundleRef mainBundle = CFBundleGetMainBundle();
CFURLRef soundFileURLRef;
soundFileURLRef =CFBundleCopyResourceURL(mainBundle, (CFStringRef) @"click", CFSTR ("WAV"), NULL);
UInt32 soundID;
AudioServicesCreateSystemSoundID(soundFileURLRef, &soundID);
AudioServicesPlaySystemSound(soundID);
}

-(IBAction)press4 {
cruzia.hidden = 0;
textarea.hidden = 0;
playbtn.hidden = 1;
tutorialbtn.hidden = 1;
optionsbtn.hidden = 1;
trainingbtn.hidden = 1;
back.hidden = 0;
cruzia.text = @"Training";
textarea.text = @"This is the training area. You can improve your Cruzia skills here!";
// declare defaults it is not declared elsewhere within your view controller
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];

// The stringForKey method returns a String and not a Boolean value
// However, if you just want to check if a value exists then it is implied you are checking for existence
// If there is no value then it will return nil and statement will fail
// You had "== YES" outside of the parenthesis which is an illegal statement
if ([defaults stringForKey:kMusic])  {
    CFBundleRef mainBundle = CFBundleGetMainBundle();
    CFURLRef soundFileURLRef;
    soundFileURLRef =CFBundleCopyResourceURL(mainBundle, (CFStringRef) @"click",                     CFSTR ("WAV"), NULL);
    UInt32 soundID;
    AudioServicesCreateSystemSoundID(soundFileURLRef, &soundID);
    AudioServicesPlaySystemSound(soundID); }
}

-(IBAction)press5 {
cruzia.hidden = 0;
textarea.hidden = 0;
playbtn.hidden = 0;
tutorialbtn.hidden = 0;
optionsbtn.hidden = 0;
trainingbtn.hidden = 0;
back.hidden = 1;
cruzia.text = @"Cruzia";
textarea.text = @"";
// declare defaults it is not declared elsewhere within your view controller
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];

// The stringForKey method returns a String and not a Boolean value
// However, if you just want to check if a value exists then it is implied you are checking for existence
// If there is no value then it will return nil and statement will fail
// You had "== YES" outside of the parenthesis which is an illegal statement
if ([defaults stringForKey:kMusic])  {
    CFBundleRef mainBundle = CFBundleGetMainBundle();
    CFURLRef soundFileURLRef;
    soundFileURLRef =CFBundleCopyResourceURL(mainBundle, (CFStringRef) @"click",                     CFSTR ("WAV"), NULL);
    UInt32 soundID;
    AudioServicesCreateSystemSoundID(soundFileURLRef, &soundID);
    AudioServicesPlaySystemSound(soundID); }

}

- (void)viewDidLoad
{
textarea.hidden = 1;
playbtn.hidden = 0;
tutorialbtn.hidden = 0;
optionsbtn.hidden = 0;
trainingbtn.hidden = 0;
back.hidden = 1;
cruzia.text = @"Cruzia";
[super viewDidLoad];

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(updateSettings:)
                                            name:
 NSUserDefaultsDidChangeNotification object:nil];

[self setupDefaults];
}

- (void)viewDidUnload 
{

[super viewDidUnload];

[[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationDidFinishLaunchingNotification object:nil];
}

-(void) setupDefaults {
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];


NSString *violenceValue = [defaults stringForKey:kViolenceMode];

if ( violenceValue == nil ) {
    NSString *pathStr = [[NSBundle mainBundle] bundlePath];
    NSString *settingsBundlePath = [pathStr stringByAppendingPathComponent:@"Settings.bundle"];
    NSString *finalPath = [settingsBundlePath stringByAppendingPathComponent:@"Root.plist"];

    NSDictionary *settingsDictionary = [NSDictionary dictionaryWithContentsOfFile:finalPath];
    NSArray *prefSpecifierArray = [settingsDictionary objectForKey:@"PreferenceSpecifiers"];


    NSString *isMusicOn, *isSoundOn;

    NSDictionary *prefItem;

    for (prefItem in prefSpecifierArray) {
        NSString *keyValue = [prefItem objectForKey:@"Key"];
        id defaultValue = [prefItem objectForKey:@"DeafultValue"];

        if ([keyValue isEqualToString:kSound])
        {
            isSoundOn = defaultValue;
        }
        else if ([keyValue isEqualToString:kMusic])
        {
            isMusicOn = defaultValue;
        }

        NSDictionary *appDefaults = [NSDictionary dictionaryWithObjectsAndKeys:                                  isSoundOn, kSound, isMusicOn, kMusic, nil];

        [defaults registerDefaults:appDefaults];
        [defaults synchronize];

    }

}

}



@end