ビルドを実行した年をcopyright表記に埋め込む for Objective-C/iOS project

AboutViewController.m

   //ビルド年を求める
    char* date = __DATE__;
    char* year = date + strlen(date) -4;
    NSInteger buildYear = atoi(year);
    
    //Copyrightの設定
    if(COPYRIGHT_FIRSTVERSION_YEAR==buildYear){
      copyright_.text = [NSString stringWithFormat:@"%@ %d %@",
                         COPYRIGHT_PREFIX, COPYRIGHT_FIRSTVERSION_YEAR, COPYRIGHT_SUFFIX];
    }else{
      copyright_.text = [NSString stringWithFormat:@"%@ %d-%d %@",
                         COPYRIGHT_PREFIX, COPYRIGHT_FIRSTVERSION_YEAR, buildYear, COPYRIGHT_SUFFIX];
    }