//Sets _squareOneNumber to 0 (this is going to be the changing value)
_squareOneNumber = 0;

if (self.squareOneNumber==0) {
    if (a==b) {
        [self gameOverImagePutter];
        NSLog(@"One wasn't pressed");
    }
}

//In touchesBegan method
UITouch *touch = [touches anyObject];
CGPoint touchLocation = [touch locationInView:self.view];

if ([self.squareOne.layer.presentationLayer hitTest:touchLocation]) {
    [_squareOne setHidden:YES];
    _squareOneNumber = 1;
}