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path: root/src/liballoc/tests/btree/mod.rs
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mod map;
mod set;

/// XorShiftRng
struct DeterministicRng {
    x: u32,
    y: u32,
    z: u32,
    w: u32,
}

impl DeterministicRng {
    fn new() -> Self {
        DeterministicRng {
            x: 0x193a6754,
            y: 0xa8a7d469,
            z: 0x97830e05,
            w: 0x113ba7bb,
        }
    }

    fn next(&mut self) -> u32 {
        let x = self.x;
        let t = x ^ (x << 11);
        self.x = self.y;
        self.y = self.z;
        self.z = self.w;
        let w_ = self.w;
        self.w = w_ ^ (w_ >> 19) ^ (t ^ (t >> 8));
        self.w
    }
}