src/libcollectionstest/btree/mod.rs

   1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 mod map;
  12 mod set;
  13
  14 /// XorShiftRng
  15 struct DeterministicRng {
  16     x: u32,
  17     y: u32,
  18     z: u32,
  19     w: u32,
  20 }
  21
  22 impl DeterministicRng {
  23     fn new() -> Self {
  24         DeterministicRng {
  25             x: 0x193a6754,
  26             y: 0xa8a7d469,
  27             z: 0x97830e05,
  28             w: 0x113ba7bb
  29         }
  30     }
  31
  32     fn next(&mut self) -> u32 {
  33         let x = self.x;
  34         let t = x ^ (x << 11);
  35         self.x = self.y;
  36         self.y = self.z;
  37         self.z = self.w;
  38         let w_ = self.w;
  39         self.w = w_ ^ (w_ >> 19) ^ (t ^ (t >> 8));
  40         self.w
  41     }
  42 }