Develop
2013.10.31 16:51
[ios] Random Thoughts: Rand() vs. arc4random()
Views 68123 Comment 0
랜덤함수 사용시..
iOS
There are several built-in randomizers on the iPhone, and most people's first thought is to use rand() after seeding it by calling
srandom(time(NULL));
But... rand() is really not a very good PRNG. random() is a little better, but still less then ideal. Fortunately, these are not the only ones available on the iPhone. Personally, I like arc4random() because it's a decent pseudo-random algorithm and has twice the range or rand().
On the iPhone, RAND_MAX is 0x7fffffff (2147483647), while arc4random() will return a maximum value of 0x100000000 (4294967296), giving much more precision. You also don't need to seed arc4random(), as the first call to it automatically seeds it.
결론은 arc4random() 을 사용하자.
[출처] http://iphonedevelopment.blogspot.com/2008/10/random-thoughts-rand-vs-arc4random.html
-
[ios] 아이폰용 앱 오픈 소스들
-
자주 쓰는 Docker 명령어 alias
-
[ios] 언어, 지역, 국가 설정 가져오기
-
베지어 곡선 (Bezier curve)
-
[ios] Start developing your navigation app for CarPlay without enrollment
-
[android] 만화 어플 소스코드
-
레고 마인드스톰 NXT 수도쿠, 큐브 소스코드..
-
디피헬만(Diffie-Hellman) 초간단 개념..
-
[c#] Hashtable <-> Json (dll 포함)
-
[C#] MD5, SHA1 해시 & 인코딩
-
[android] 점심 해결 앱 소스 코드 ㅋㅋ
-
[android] XML파서(XMLParser)의 종류와 성능 비교에 대한 발표 자료