v/vlib/rand/rand.v

34 lines
602 B
V
Raw Normal View History

2019-06-23 04:21:30 +02:00
// Copyright (c) 2019 Alexander Medvednikov. All rights reserved.
// Use of this source code is governed by an MIT license
// that can be found in the LICENSE file.
2019-06-22 20:20:28 +02:00
module rand
pub fn seed(s int) {
C.srand(s)
2019-06-22 20:20:28 +02:00
}
pub fn next(max int) int {
return C.rand() % max
2019-06-22 20:20:28 +02:00
}
2019-09-16 21:21:21 +02:00
fn C.rand() int
/**
* rand_r - reentrant pseudo-random number generator
*
* @param seed byref reentrant seed, holding current state
*
* @return a value between 0 and C.RAND_MAX (inclusive)
*/
2019-12-19 22:29:37 +01:00
2019-09-16 21:21:21 +02:00
pub fn rand_r(seed &int) int {
2019-12-19 22:29:37 +01:00
unsafe{
mut rs := seed
ns := (*rs * 1103515245 + 12345)
*rs = ns
return ns & 0x7fffffff
2019-11-10 17:57:17 +01:00
}
2019-09-16 21:21:21 +02:00
}
2019-12-19 22:29:37 +01:00