Generating random numbers in Objective-C -

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i'm java head mainly, , want way generate pseudo-random number between 0 , 74. in java use method:

random.nextint(74)

i'm not interested in discussion seeds or true randomness, how accomplish same task in objective-c. i've scoured google, , there seems lots of different , conflicting bits of information.

you should use arc4random_uniform() function. uses superior algorithm rand. don't need set seed.

#include <stdlib.h> // ... // ... int r = arc4random_uniform(74);

the arc4random man page:

name      arc4random, arc4random_stir, arc4random_addrandom -- arc4 random number generator  library      standard c library (libc, -lc)  synopsis      #include <stdlib.h>       u_int32_t      arc4random(void);       void      arc4random_stir(void);       void      arc4random_addrandom(unsigned char *dat, int datlen);  description      arc4random() function uses key stream generator employed arc4 cipher, uses 8*8 8      bit s-boxes.  s-boxes can in (2**1700) states.  arc4random() function returns pseudo-      random numbers in range of 0 (2**32)-1, , therefore has twice range of rand(3) ,      random(3).       arc4random_stir() function reads data /dev/urandom , uses permute s-boxes via      arc4random_addrandom().       there no need call arc4random_stir() before using arc4random(), since arc4random() automatically      initializes itself.  examples      following produces drop-in replacement traditional rand() , random() functions using      arc4random():             #define foo4random() (arc4random() % ((unsigned)rand_max + 1))

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